How to Identify Hydraulic Fittings: Measure Threads and Seats

Say where the threads are and how the end seals, then pick the thread you measured. You’ll get the fitting it most likely is, what else it could be, and the check that tells them apart.

Where are the threads?

On the outsideA male end: a fitting, adapter or hose end with threads you can see Inside a nut that spinsA female swivel, usually on the end of a hose Inside a portThreads in a pump, valve, cylinder or block on the machine It’s a water line, not hydraulicsA faucet, hose, toilet or pipe: use the plumbing identifier

Do the threads narrow as they go in?

Measure across the threads at the mouth and a few threads in.

Yes, they narrow (tapered)A pipe-thread port, sealed on the threads No, they’re straightThe same width all the way in Not sureCan’t measure inside the port

Which kind of thread?

Try each pitch gauge against the threads until one matches. Holding them against a light helps.

BSP: 28, 19, 14 or 11 per inchA British (Whitworth) gauge fits Inch UN: 24, 20, 18, 16, 14 or 12 per inchA US (Unified) gauge fits Metric: 1.5 or 2 mmA metric gauge fits

Which thread is it?

Count threads per inch, then measure across the threads of the male part.

5/16-2424 per inch, male about 7.9 mm (.312")3/8-2424 per inch, male about 9.5 mm (.375"), female about 8.6 mm 7/16-2020 per inch, male about 11.1 mm (.437"), female about 10.0 mm 1/2-2020 per inch, male about 12.7 mm (.500"), female about 11.6 mm 9/16-1818 per inch, male about 14.3 mm (.562"), female about 13.0 mm 3/4-1616 per inch, male about 19.1 mm (.752"), female about 17.6 mm 7/8-1414 per inch, male about 22.2 mm (.875"), female about 20.5 mm 1 1/16-1212 per inch, male about 27.0 mm (1.063"), female about 24.6 mm 1 3/16-1212 per inch, male about 30.1 mm (1.185"), female about 28.3 mm 1 5/16-1212 per inch, male about 33.3 mm (1.311"), female about 31.3 mm 1 5/8-1212 per inch, male about 41.3 mm (1.626"), female about 39.2 mm 1 7/8-1212 per inch, male about 47.6 mm (1.874"), female about 45.6 mm

Which size is it?

Measure across the threads.

1/8" BSP, 28 per inchmale about 9.7 mm (.382"), female about 8.6 mm 1/4" BSP, 19 per inchmale about 13.2 mm (.520"), female about 11.5 mm 3/8" BSP, 19 per inchmale about 16.7 mm (.657"), female about 14.9 mm 1/2" BSP, 14 per inchmale about 20.9 mm (.823"), female about 18.6 mm 3/4" BSP, 14 per inchmale about 26.4 mm (1.039"), female about 24.1 mm 1" BSP, 11 per inchmale about 33.2 mm (1.307"), female about 30.3 mm

Threads per inch, and the width across them?

Measure a male part at the fourth or fifth thread. In a port, measure across the threads at the mouth.

27 per inch, about 0.40"Male about 0.401" (10.2 mm), female about 0.34"28 per inch, about 0.38"Male about 0.383" (9.7 mm), female about 0.34"18 per inch, about 0.53"Male about 0.533" (13.5 mm), female about 0.44"19 per inch, about 0.52"Male about 0.518" (13.2 mm), female about 0.45"18 per inch, about 0.67"Male about 0.668" (17.0 mm), female about 0.57"19 per inch, about 0.66"Male about 0.656" (16.7 mm), female about 0.59"14 per inch, about 0.83"Male about 0.832" (21.1 mm), female about 0.70"14 per inch, about 1.04"Male about 1.043" (26.5 mm), female about 0.91"11.5 per inch, about 1.30"Male about 1.305" (33.1 mm), female about 1.15"11 per inch, about 1.31"Male about 1.309" (33.2 mm), female about 1.19"

What’s inside the nut?

Look past the threads at the part the nut holds.

A cone-shaped seatAn angled sealing face inside, behind the threads A flat faceFlat and smooth: the O-ring is on the part it screws onto Not sureCan’t see a seat, or it doesn’t look like these

Which thread is it?

Count threads per inch, then measure across the threads.

9/16-1818 per inch, male about 14.2 mm (.559"), female about 13.0 mm 11/16-1616 per inch, male about 17.5 mm (.689"), female about 15.9 mm 13/16-1616 per inch, male about 20.6 mm (.811"), female about 19.1 mm 1-1414 per inch, male about 25.4 mm (1.000"), female about 23.8 mm 1 3/16-1212 per inch, male about 30.1 mm (1.185"), female about 28.2 mm 1 7/16-1212 per inch, male about 36.5 mm (1.437"), female about 34.1 mm 1 11/16-1212 per inch, male about 42.9 mm (1.689"), female about 40.5 mm 2-1212 per inch, male about 50.8 mm (2.000"), female about 48.8 mm

Which seat gauge lies flat on it?

Hold the gauge on the sealing face. When the gauge and the fitting line up straight, that’s the angle.

37°SAE 37° flare (JIC)45°SAE 45° flare 30°Often on Japanese and Korean machines 24°A metric cone, with or without an O-ring I don’t have a seat gauge37° and 45° look alike by eye

Which metric thread is it?

Measure across the threads in mm, and check the pitch with a metric gauge.

M12×1.5Light series, 6 mm tube M14×1.5Light series for 8 mm tube or heavy for 6 mm M16×1.5Light series for 10 mm tube or heavy for 8 mm M18×1.5Light series for 12 mm tube or heavy for 10 mm M20×1.5Heavy series, 12 mm tube M22×1.5Light series for 15 mm tube or heavy for 14 mm M24×1.5Heavy series, 16 mm tube M26×1.5Light series, 18 mm tube M30×2Light series for 22 mm tube or heavy for 20 mm M36×2Light series for 28 mm tube or heavy for 25 mm M42×2Heavy series, 30 mm tube M45×2Light series, 35 mm tube M52×2Light series for 42 mm tube or heavy for 38 mm

Which kind of thread?

Check with an inch pitch gauge, a British one and a metric one.

BSP: 28, 19, 14 or 11 per inchA British (Whitworth) gauge fits Metric, 1.5 mmA metric gauge fits Inch pipe: 27, 18, 14 or 11.5 per inchA US gauge fits: an NPTF male or NPSM swivel

Which thread is it?

Use a pitch gauge for the threads per inch and a caliper for the width.

7/16-2020 per inch, male about 11.1 mm (.437"), female about 9.9 mm 1/2-2020 per inch, male about 12.7 mm (.500"), female about 11.5 mm 5/8-1818 per inch, male about 15.9 mm (.626"), female about 14.3 mm 3/4-1616 per inch, male about 19.1 mm (.752"), female about 17.5 mm 7/8-1414 per inch, male about 22.2 mm (.874"), female about 20.6 mm 1 1/16-1414 per inch, male about 27.0 mm (1.063"), female about 25.0 mm

Which thread is it?

Count threads per inch with a pitch gauge, then measure across the threads with a caliper.

7/16-2020 per inch, male about 11.1 mm (.437"), female about 10.0 mm 1/2-2020 per inch, male about 12.7 mm (.500"), female about 11.6 mm 9/16-1818 per inch, male about 14.3 mm (.563"), female about 13.0 mm 3/4-1616 per inch, male about 19.1 mm (.752"), female about 17.6 mm 7/8-1414 per inch, male about 22.2 mm (.874"), female about 20.5 mm 1 1/16-1212 per inch, male about 27.0 mm (1.063"), female about 24.6 mm 1 3/16-1212 per inch, male about 30.1 mm (1.185"), female about 28.3 mm 1 5/16-1212 per inch, male about 33.3 mm (1.311"), female about 31.3 mm 1 5/8-1212 per inch, male about 41.3 mm (1.626"), female about 39.2 mm 1 7/8-1212 per inch, male about 47.6 mm (1.874"), female about 45.6 mm

What does the end look like?

Look at the very end and just behind the threads.

Threads that narrow toward the tipNothing else: no cone, O-ring or washer A cone on the noseA smooth, angled nose in front of the threads An O-ring behind the threadsA rubber ring at the base of the threads, against a flat shoulder An O-ring in the flat end faceA rubber ring set into a groove in the flat end A washer or seal under the hexStraight threads, sealing against a flat face Not sureCan’t tell, or it doesn’t look like these

You most likely have

Measure it, or take it in

Hydraulic threads look alike, so they have to be measured: count the threads per inch, measure across the threads and check how the end seals.

Available on Amazon

Hydraulic thread identification kit

Compare the part with the one it replaces, or measure the port or thread it goes on.
A thread identification kit puts pitch gauges and a caliper in one case, and some add seat gauges.

If you can’t be sure, take the part to a hydraulic hose shop to be matched.

Next

Hydraulic thread chart JIC vs ORB vs ORFS

You most likely have

A metric straight thread

A metric straight thread, as on a metric port or stud end. It seals with an O-ring or washer, not the thread.

Available on Amazon

Thread pitch gauge, SAE and metric

Metric straight-thread ports also come in several sealing styles. Measure the thread in mm and note how it seals.
A hydraulic hose shop can match a metric part with the one it replaces.

Metric threads are named by the outside diameter and the pitch, such as M22×1.5 (22 mm across, 1.5 mm between threads).

Next

Hydraulic thread chart

You most likely have

-2 ORB (O-ring boss), 5/16-24

A -2 SAE straight-thread O-ring boss end: the male has an O-ring at the base of its 5/16-24 thread, screws into a port and seals on the O-ring, not the thread.

A -2 JIC 37° fitting has the same thread with a cone on the nose, so a cone and no O-ring means JIC.
Check the -2 port’s sealing face as well: straight-thread ports come in several sealing styles that can look alike.

Across the threads, a -2 ORB male measures about 7.9 mm (.312"). Keep tape and sealant off the -2 straight thread.

Next

JIC vs ORB vs ORFS Hydraulic thread chart

You most likely have

-3 ORB (O-ring boss), 3/8-24

A -3 SAE straight-thread O-ring boss end: the male has an O-ring at the base of its 3/8-24 thread, screws into a port and seals on the O-ring, not the thread.

A -3 JIC 37° fitting has the same thread with a cone on the nose, so a cone and no O-ring means JIC.
Check the -3 port’s sealing face as well: straight-thread ports come in several sealing styles that can look alike.

Across the threads, a -3 ORB male measures about 9.5 mm (.375"). Keep tape and sealant off the -3 straight thread.

Next

JIC vs ORB vs ORFS Hydraulic thread chart

You most likely have

-4 ORB (O-ring boss), 7/16-20

A -4 SAE straight-thread O-ring boss end: the male has an O-ring at the base of its 7/16-20 thread, screws into a port and seals on the O-ring, not the thread.

A -4 JIC 37° fitting has the same thread with a cone on the nose, so a cone and no O-ring means JIC.
Check the -4 port’s sealing face as well: straight-thread ports come in several sealing styles that can look alike.

Across the threads, a -4 ORB male measures about 11.1 mm (.437"). Keep tape and sealant off the -4 straight thread.

Next

Adapters for a -4 ORB port JIC vs ORB vs ORFS Hydraulic thread chart

You most likely have

-5 ORB (O-ring boss), 1/2-20

A -5 SAE straight-thread O-ring boss end: the male has an O-ring at the base of its 1/2-20 thread, screws into a port and seals on the O-ring, not the thread.

A -5 JIC 37° fitting has the same thread with a cone on the nose, so a cone and no O-ring means JIC.
Check the -5 port’s sealing face as well: straight-thread ports come in several sealing styles that can look alike.

Across the threads, a -5 ORB male measures about 12.7 mm (.500"). Keep tape and sealant off the -5 straight thread.

Next

Adapters for a -5 ORB port JIC vs ORB vs ORFS Hydraulic thread chart

You most likely have

-6 ORB (O-ring boss), 9/16-18

A -6 SAE straight-thread O-ring boss end: the male has an O-ring at the base of its 9/16-18 thread, screws into a port and seals on the O-ring, not the thread.

A -6 JIC 37° fitting has the same thread with a cone on the nose, so a cone and no O-ring means JIC.
Check the -6 port’s sealing face as well: straight-thread ports come in several sealing styles that can look alike.

Across the threads, a -6 ORB male measures about 14.3 mm (.562"). Keep tape and sealant off the -6 straight thread.

Next

Adapters for a -6 ORB port JIC vs ORB vs ORFS Hydraulic thread chart

You most likely have

-8 ORB (O-ring boss), 3/4-16

A -8 SAE straight-thread O-ring boss end: the male has an O-ring at the base of its 3/4-16 thread, screws into a port and seals on the O-ring, not the thread.

A -8 JIC 37° fitting has the same thread with a cone on the nose, so a cone and no O-ring means JIC.
Check the -8 port’s sealing face as well: straight-thread ports come in several sealing styles that can look alike.

Across the threads, a -8 ORB male measures about 19.1 mm (.752"). Keep tape and sealant off the -8 straight thread.

Next

Adapters for a -8 ORB port JIC vs ORB vs ORFS Hydraulic thread chart

You most likely have

-10 ORB (O-ring boss), 7/8-14

A -10 SAE straight-thread O-ring boss end: the male has an O-ring at the base of its 7/8-14 thread, screws into a port and seals on the O-ring, not the thread.

A -10 JIC 37° fitting has the same thread with a cone on the nose, so a cone and no O-ring means JIC.
Check the -10 port’s sealing face as well: straight-thread ports come in several sealing styles that can look alike.

Across the threads, a -10 ORB male measures about 22.2 mm (.875"). Keep tape and sealant off the -10 straight thread.

Next

Adapters for a -10 ORB port JIC vs ORB vs ORFS Hydraulic thread chart

You most likely have

-12 ORB (O-ring boss), 1 1/16-12

A -12 SAE straight-thread O-ring boss end: the male has an O-ring at the base of its 1 1/16-12 thread, screws into a port and seals on the O-ring, not the thread.

A -12 JIC 37° fitting has the same thread with a cone on the nose, so a cone and no O-ring means JIC.
Check the -12 port’s sealing face as well: straight-thread ports come in several sealing styles that can look alike.

Across the threads, a -12 ORB male measures about 27.0 mm (1.063"). Keep tape and sealant off the -12 straight thread.

Next

Adapters for a -12 ORB port JIC vs ORB vs ORFS Hydraulic thread chart

You most likely have

-14 ORB (O-ring boss), 1 3/16-12

A -14 SAE straight-thread O-ring boss end: the male has an O-ring at the base of its 1 3/16-12 thread, screws into a port and seals on the O-ring, not the thread.

A -14 JIC 37° fitting has the same thread with a cone on the nose, so a cone and no O-ring means JIC.
Check the -14 port’s sealing face as well: straight-thread ports come in several sealing styles that can look alike.

Across the threads, a -14 ORB male measures about 30.1 mm (1.185"). Keep tape and sealant off the -14 straight thread.

Next

JIC vs ORB vs ORFS Hydraulic thread chart

You most likely have

-16 ORB (O-ring boss), 1 5/16-12

A -16 SAE straight-thread O-ring boss end: the male has an O-ring at the base of its 1 5/16-12 thread, screws into a port and seals on the O-ring, not the thread.

A -16 JIC 37° fitting has the same thread with a cone on the nose, so a cone and no O-ring means JIC.
Check the -16 port’s sealing face as well: straight-thread ports come in several sealing styles that can look alike.

Across the threads, a -16 ORB male measures about 33.3 mm (1.311"). Keep tape and sealant off the -16 straight thread.

Next

Adapters for a -16 ORB port JIC vs ORB vs ORFS Hydraulic thread chart

You most likely have

-20 ORB (O-ring boss), 1 5/8-12

A -20 SAE straight-thread O-ring boss end: the male has an O-ring at the base of its 1 5/8-12 thread, screws into a port and seals on the O-ring, not the thread.

A -20 JIC 37° fitting has the same thread with a cone on the nose, so a cone and no O-ring means JIC.
Check the -20 port’s sealing face as well: straight-thread ports come in several sealing styles that can look alike.

Across the threads, a -20 ORB male measures about 41.3 mm (1.626"). Keep tape and sealant off the -20 straight thread.

Next

JIC vs ORB vs ORFS Hydraulic thread chart

You most likely have

-24 ORB (O-ring boss), 1 7/8-12

A -24 SAE straight-thread O-ring boss end: the male has an O-ring at the base of its 1 7/8-12 thread, screws into a port and seals on the O-ring, not the thread.

A -24 JIC 37° fitting has the same thread with a cone on the nose, so a cone and no O-ring means JIC.
Check the -24 port’s sealing face as well: straight-thread ports come in several sealing styles that can look alike.

Across the threads, a -24 ORB male measures about 47.6 mm (1.874"). Keep tape and sealant off the -24 straight thread.

Next

JIC vs ORB vs ORFS Hydraulic thread chart

You most likely have

1/8" BSPP (G1/8) straight thread

A 1/8" British parallel pipe thread, 28 per inch, which only holds the parts together: the seal is a washer or O-ring on a flat face, or a cone.

Check how the 1/8" end seals: a flat face with a bonded washer or O-ring makes it a BSPP port end.
A 30° seat or 60° cone on a 1/8" BSP thread is a cone fitting, JIS or BS 5200 (K4), and those two look alike but don’t interchange.
Keep tape and sealant off the 1/8" straight thread.

Across the 1/8" BSPP threads: male about 9.7 mm (.382"), female about 8.6 mm.

Next

Adapters for a 1/8" BSPP port NPT vs BSP on hydraulics Hydraulic thread chart

You most likely have

1/4" BSPP (G1/4) straight thread

A 1/4" British parallel pipe thread, 19 per inch, which only holds the parts together: the seal is a washer or O-ring on a flat face, or a cone.

Check how the 1/4" end seals: a flat face with a bonded washer or O-ring makes it a BSPP port end.
A 30° seat or 60° cone on a 1/4" BSP thread is a cone fitting, JIS or BS 5200 (K4), and those two look alike but don’t interchange.
Keep tape and sealant off the 1/4" straight thread.

Across the 1/4" BSPP threads: male about 13.2 mm (.520"), female about 11.5 mm.

Next

Adapters for a 1/4" BSPP port NPT vs BSP on hydraulics Hydraulic thread chart

You most likely have

3/8" BSPP (G3/8) straight thread

A 3/8" British parallel pipe thread, 19 per inch, which only holds the parts together: the seal is a washer or O-ring on a flat face, or a cone.

Check how the 3/8" end seals: a flat face with a bonded washer or O-ring makes it a BSPP port end.
A 30° seat or 60° cone on a 3/8" BSP thread is a cone fitting, JIS or BS 5200 (K4), and those two look alike but don’t interchange.
Keep tape and sealant off the 3/8" straight thread.

Across the 3/8" BSPP threads: male about 16.7 mm (.657"), female about 14.9 mm.

Next

Adapters for a 3/8" BSPP port NPT vs BSP on hydraulics Hydraulic thread chart

You most likely have

1/2" BSPP (G1/2) straight thread

A 1/2" British parallel pipe thread, 14 per inch, which only holds the parts together: the seal is a washer or O-ring on a flat face, or a cone.

Check how the 1/2" end seals: a flat face with a bonded washer or O-ring makes it a BSPP port end.
A 30° seat or 60° cone on a 1/2" BSP thread is a cone fitting, JIS or BS 5200 (K4), and those two look alike but don’t interchange.
Keep tape and sealant off the 1/2" straight thread.

Across the 1/2" BSPP threads: male about 20.9 mm (.823"), female about 18.6 mm.

Next

Adapters for a 1/2" BSPP port NPT vs BSP on hydraulics Hydraulic thread chart

You most likely have

3/4" BSPP (G3/4) straight thread

A 3/4" British parallel pipe thread, 14 per inch, which only holds the parts together: the seal is a washer or O-ring on a flat face, or a cone.

Check how the 3/4" end seals: a flat face with a bonded washer or O-ring makes it a BSPP port end.
A 30° seat or 60° cone on a 3/4" BSP thread is a cone fitting, JIS or BS 5200 (K4), and those two look alike but don’t interchange.
Keep tape and sealant off the 3/4" straight thread.

Across the 3/4" BSPP threads: male about 26.4 mm (1.039"), female about 24.1 mm.

Next

Adapters for a 3/4" BSPP port NPT vs BSP on hydraulics Hydraulic thread chart

You most likely have

1" BSPP (G1) straight thread

A 1" British parallel pipe thread, 11 per inch, which only holds the parts together: the seal is a washer or O-ring on a flat face, or a cone.

Check how the 1" end seals: a flat face with a bonded washer or O-ring makes it a BSPP port end.
A 30° seat or 60° cone on a 1" BSP thread is a cone fitting, JIS or BS 5200 (K4), and those two look alike but don’t interchange.
Keep tape and sealant off the 1" straight thread.

Across the 1" BSPP threads: male about 33.2 mm (1.307"), female about 30.3 mm.

Next

Adapters for a 1" BSPP port NPT vs BSP on hydraulics Hydraulic thread chart

You most likely have

1/8" NPT (or NPTF) pipe thread

A 1/8" tapered pipe thread, 27 threads per inch. It seals on the threads.

Available on Amazon

Thread pitch gauge, SAE and metric

1/8" BSPT is close: 28 threads per inch instead of 27, so check with both an inch and a British pitch gauge.
1/8" NPTF (dryseal) has the same size and thread count as NPT, and both need a sealant on the threads.

Male about 0.401" (10.2 mm), female about 0.336".

Next

Adapters for a 1/8" NPT port NPT vs BSP on hydraulics Hydraulic thread chart

You most likely have

1/8" BSPT pipe thread

A 1/8" British tapered pipe thread, 28 threads per inch, sealing on the threads.

Available on Amazon

Thread pitch gauge, SAE and metric

1/8" NPT is close: 27 threads per inch instead of 28, so check the count with both gauges.
Make sure the 1/8" thread really narrows: a straight British thread is BSPP, which seals with a washer, O-ring or cone instead.

Male about 0.383" (9.7 mm), female about 0.337"; at 1/8" the BSPT thread is cut at 55° and the NPT at 60°.

Next

NPT vs BSP on hydraulics Hydraulic thread chart

You most likely have

1/4" NPT (or NPTF) pipe thread

A 1/4" tapered pipe thread, 18 threads per inch. It seals on the threads.

Available on Amazon

Thread pitch gauge, SAE and metric

1/4" BSPT is close: 19 threads per inch instead of 18, so check with both an inch and a British pitch gauge.
1/4" NPTF (dryseal) has the same size and thread count as NPT, and both need a sealant on the threads.

Male about 0.533" (13.5 mm), female about 0.436".

Next

Adapters for a 1/4" NPT port NPT vs BSP on hydraulics Hydraulic thread chart

You most likely have

1/4" BSPT pipe thread

A 1/4" British tapered pipe thread, 19 threads per inch, sealing on the threads.

Available on Amazon

Thread pitch gauge, SAE and metric

1/4" NPT is close: 18 threads per inch instead of 19, so check the count with both gauges.
Make sure the 1/4" thread really narrows: a straight British thread is BSPP, which seals with a washer, O-ring or cone instead.

Male about 0.518" (13.2 mm), female about 0.451"; at 1/4" the BSPT thread is cut at 55° and the NPT at 60°.

Next

NPT vs BSP on hydraulics Hydraulic thread chart

You most likely have

3/8" NPT (or NPTF) pipe thread

A 3/8" tapered pipe thread, 18 threads per inch. It seals on the threads.

Available on Amazon

Thread pitch gauge, SAE and metric

3/8" BSPT is close: 19 threads per inch instead of 18, so check with both an inch and a British pitch gauge.
3/8" NPTF (dryseal) has the same size and thread count as NPT, and both need a sealant on the threads.

Male about 0.668" (17.0 mm), female about 0.571".

Next

Adapters for a 3/8" NPT port NPT vs BSP on hydraulics Hydraulic thread chart

You most likely have

3/8" BSPT pipe thread

A 3/8" British tapered pipe thread, 19 threads per inch, sealing on the threads.

Available on Amazon

Thread pitch gauge, SAE and metric

3/8" NPT is close: 18 threads per inch instead of 19, so check the count with both gauges.
Make sure the 3/8" thread really narrows: a straight British thread is BSPP, which seals with a washer, O-ring or cone instead.

Male about 0.656" (16.7 mm), female about 0.589"; at 3/8" the BSPT thread is cut at 55° and the NPT at 60°.

Next

NPT vs BSP on hydraulics Hydraulic thread chart

You most likely have

1/2" NPT or BSPT pipe thread

A 1/2" tapered pipe thread, 14 per inch. NPT and BSPT at 1/2" have the same count, and their male threads measure less than 0.2 mm apart.

Available on Amazon

Hydraulic thread identification kit

Measuring can’t settle this one. At 1/2" the two threads are so close in design that a positive identification can take an optical comparator.
Look for markings on the 1/2" part or the machine, or check the machine’s parts list.
If the 1/2" part still can’t be identified, take it to a hydraulic hose shop to be matched.

NPT male about 0.832" (21.1 mm), BSPT male about 0.825" (21.0 mm); at 1/2" the NPT thread is cut at 60° and the BSPT at 55°.

Next

NPT vs BSP on hydraulics Hydraulic thread chart

You most likely have

3/4" NPT or BSPT pipe thread

A 3/4" tapered pipe thread, 14 per inch. NPT and BSPT at 3/4" have the same count, and their male threads measure less than 0.2 mm apart.

Available on Amazon

Hydraulic thread identification kit

Measuring can’t settle this one. At 3/4" the two threads are so close in design that a positive identification can take an optical comparator.
Look for markings on the 3/4" part or the machine, or check the machine’s parts list.
If the 3/4" part still can’t be identified, take it to a hydraulic hose shop to be matched.

NPT male about 1.043" (26.5 mm), BSPT male about 1.041" (26.4 mm); at 3/4" the NPT thread is cut at 60° and the BSPT at 55°.

Next

NPT vs BSP on hydraulics Hydraulic thread chart

You most likely have

1" NPT (or NPTF) pipe thread

A 1" tapered pipe thread, 11.5 threads per inch. It seals on the threads.

Available on Amazon

Thread pitch gauge, SAE and metric

1" BSPT is close: 11 threads per inch instead of 11.5, so check with both an inch and a British pitch gauge.
1" NPTF (dryseal) has the same size and thread count as NPT, and both need a sealant on the threads.

Male about 1.305" (33.1 mm), female about 1.148".

Next

Adapters for a 1" NPT port NPT vs BSP on hydraulics Hydraulic thread chart

You most likely have

1" BSPT pipe thread

A 1" British tapered pipe thread, 11 threads per inch, sealing on the threads.

Available on Amazon

Thread pitch gauge, SAE and metric

1" NPT is close: 11.5 threads per inch instead of 11, so check the count with both gauges.
Make sure the 1" thread really narrows: a straight British thread is BSPP, which seals with a washer, O-ring or cone instead.

Male about 1.309" (33.2 mm), female about 1.193"; at 1" the BSPT thread is cut at 55° and the NPT at 60°.

Next

NPT vs BSP on hydraulics Hydraulic thread chart

You most likely have

-4 ORFS (O-ring face seal), 9/16-18

A -4 O-ring face seal fitting for 1/4" tube, with a straight 9/16-18 thread, sealing on the O-ring in its flat face.

Its 9/16-18 thread is also on -6 JIC and ORB fittings; the flat face and its O-ring make this one ORFS.
On a -4 ORFS pair the O-ring sits in the male’s flat face, and the female swivel has a plain flat face inside its nut.

Across the 9/16-18 threads: male about 14.2 mm (.559"), female about 13.0 mm.

Next

Adapters for a -4 ORFS hose end JIC vs ORB vs ORFS Hydraulic thread chart

You most likely have

-6 ORFS (O-ring face seal), 11/16-16

A -6 O-ring face seal fitting for 3/8" tube, with a straight 11/16-16 thread, sealing on the O-ring in its flat face.

On a -6 ORFS pair the O-ring sits in the male’s flat face, and the female swivel has a plain flat face inside its nut.

Across the 11/16-16 threads: male about 17.5 mm (.689"), female about 15.9 mm.

Next

Adapters for a -6 ORFS hose end JIC vs ORB vs ORFS Hydraulic thread chart

You most likely have

-8 ORFS (O-ring face seal), 13/16-16

A -8 O-ring face seal fitting for 1/2" tube, with a straight 13/16-16 thread, sealing on the O-ring in its flat face.

On a -8 ORFS pair the O-ring sits in the male’s flat face, and the female swivel has a plain flat face inside its nut.

Across the 13/16-16 threads: male about 20.6 mm (.811"), female about 19.1 mm.

Next

Adapters for a -8 ORFS hose end JIC vs ORB vs ORFS Hydraulic thread chart

You most likely have

-10 ORFS (O-ring face seal), 1-14

A -10 O-ring face seal fitting for 5/8" tube, with a straight 1-14 thread, sealing on the O-ring in its flat face.

On a -10 ORFS pair the O-ring sits in the male’s flat face, and the female swivel has a plain flat face inside its nut.

Across the 1-14 threads: male about 25.4 mm (1.000"), female about 23.8 mm.

Next

Adapters for a -10 ORFS hose end JIC vs ORB vs ORFS Hydraulic thread chart

You most likely have

-12 ORFS (O-ring face seal), 1 3/16-12

A -12 O-ring face seal fitting for 3/4" tube, with a straight 1 3/16-12 thread, sealing on the O-ring in its flat face.

Its 1 3/16-12 thread is also on -14 JIC and ORB fittings; the flat face and its O-ring make this one ORFS.
On a -12 ORFS pair the O-ring sits in the male’s flat face, and the female swivel has a plain flat face inside its nut.

Across the 1 3/16-12 threads: male about 30.1 mm (1.185"), female about 28.2 mm.

Next

Adapters for a -12 ORFS hose end JIC vs ORB vs ORFS Hydraulic thread chart

You most likely have

-16 ORFS (O-ring face seal), 1 7/16-12

A -16 O-ring face seal fitting for 1" tube, with a straight 1 7/16-12 thread, sealing on the O-ring in its flat face.

On a -16 ORFS pair the O-ring sits in the male’s flat face, and the female swivel has a plain flat face inside its nut.

Across the 1 7/16-12 threads: male about 36.5 mm (1.437"), female about 34.1 mm.

Next

Adapters for a -16 ORFS hose end JIC vs ORB vs ORFS Hydraulic thread chart

You most likely have

-20 ORFS (O-ring face seal), 1 11/16-12

A -20 O-ring face seal fitting for 1 1/4" tube, with a straight 1 11/16-12 thread, sealing on the O-ring in its flat face.

On a -20 ORFS pair the O-ring sits in the male’s flat face, and the female swivel has a plain flat face inside its nut.

Across the 1 11/16-12 threads: male about 42.9 mm (1.689"), female about 40.5 mm.

Next

JIC vs ORB vs ORFS Hydraulic thread chart

You most likely have

-24 ORFS (O-ring face seal), 2-12

A -24 O-ring face seal fitting for 1 1/2" tube, with a straight 2-12 thread, sealing on the O-ring in its flat face.

On a -24 ORFS pair the O-ring sits in the male’s flat face, and the female swivel has a plain flat face inside its nut.

Across the 2-12 threads: male about 50.8 mm (2.000"), female about 48.8 mm.

Next

JIC vs ORB vs ORFS Hydraulic thread chart

You most likely have

A 37° or 45° flare, most likely

Without a seat gauge you can measure the thread, but at most sizes the thread doesn’t settle it.

Available on Amazon

Hydraulic seat angle gauge

JIC 37° and SAE 45° share the same thread at -2, -3, -4, -5, -8 and -10, and the two don’t seal on each other.
A seat angle gauge settles it: hold it on the cone or seat until the gauge and the fitting line up straight.

Or take the fitting to a hydraulic hose shop, which can check the seat for you.

Next

JIC vs ORB vs ORFS Hydraulic thread chart

You most likely have

M12×1.5 metric 24° cone (DIN)

A metric 24° cone fitting with an M12×1.5 thread. Parker’s table lists it only as 6L (light series, 6 mm tube).

Available on Amazon

Thread pitch gauge, SAE and metric

Measure the outside diameter of the tube too: the M12×1.5 thread alone doesn’t tell a light-series fitting from a heavy one.
French metric (“GAZ”) fittings also have a 24° seat: if the M12×1.5 part doesn’t match DIN, have a hydraulic hose shop check it.

Metric threads are named by their outside diameter and pitch: M12x1.5 is 12 mm across with 1.5 mm between threads.

Next

Hydraulic thread chart

You most likely have

M14×1.5 metric 24° cone (DIN)

A metric 24° cone fitting with an M14×1.5 thread. This thread is on two sizes: 8L (light series, 8 mm tube) and 6S (heavy series, 6 mm tube).

Available on Amazon

Thread pitch gauge, SAE and metric

Measure the outside diameter of the tube too: the M14×1.5 thread alone doesn’t tell a light-series fitting from a heavy one.
French metric (“GAZ”) fittings also have a 24° seat: if the M14×1.5 part doesn’t match DIN, have a hydraulic hose shop check it.

Metric threads are named by their outside diameter and pitch: M14x1.5 is 14 mm across with 1.5 mm between threads.

Next

Hydraulic thread chart

You most likely have

M16×1.5 metric 24° cone (DIN)

A metric 24° cone fitting with an M16×1.5 thread. This thread is on two sizes: 10L (light series, 10 mm tube) and 8S (heavy series, 8 mm tube).

Available on Amazon

Thread pitch gauge, SAE and metric

Measure the outside diameter of the tube too: the M16×1.5 thread alone doesn’t tell a light-series fitting from a heavy one.
French metric (“GAZ”) fittings also have a 24° seat: if the M16×1.5 part doesn’t match DIN, have a hydraulic hose shop check it.

Metric threads are named by their outside diameter and pitch: M16x1.5 is 16 mm across with 1.5 mm between threads.

Next

Hydraulic thread chart

You most likely have

M18×1.5 metric 24° cone (DIN)

A metric 24° cone fitting with an M18×1.5 thread. This thread is on two sizes: 12L (light series, 12 mm tube) and 10S (heavy series, 10 mm tube).

Available on Amazon

Thread pitch gauge, SAE and metric

Measure the outside diameter of the tube too: the M18×1.5 thread alone doesn’t tell a light-series fitting from a heavy one.
French metric (“GAZ”) fittings also have a 24° seat: if the M18×1.5 part doesn’t match DIN, have a hydraulic hose shop check it.

Metric threads are named by their outside diameter and pitch: M18x1.5 is 18 mm across with 1.5 mm between threads.

Next

Hydraulic thread chart

You most likely have

M20×1.5 metric 24° cone (DIN)

A metric 24° cone fitting with an M20×1.5 thread. Parker’s table lists it only as 12S (heavy series, 12 mm tube).

Available on Amazon

Thread pitch gauge, SAE and metric

Measure the outside diameter of the tube too: the M20×1.5 thread alone doesn’t tell a light-series fitting from a heavy one.
French metric (“GAZ”) fittings also have a 24° seat: if the M20×1.5 part doesn’t match DIN, have a hydraulic hose shop check it.

Metric threads are named by their outside diameter and pitch: M20x1.5 is 20 mm across with 1.5 mm between threads.

Next

Hydraulic thread chart

You most likely have

M22×1.5 metric 24° cone (DIN)

A metric 24° cone fitting with an M22×1.5 thread. This thread is on two sizes: 15L (light series, 15 mm tube) and 14S (heavy series, 14 mm tube).

Available on Amazon

Thread pitch gauge, SAE and metric

Measure the outside diameter of the tube too: the M22×1.5 thread alone doesn’t tell a light-series fitting from a heavy one.
French metric (“GAZ”) fittings also have a 24° seat: if the M22×1.5 part doesn’t match DIN, have a hydraulic hose shop check it.

Metric threads are named by their outside diameter and pitch: M22x1.5 is 22 mm across with 1.5 mm between threads.

Next

Hydraulic thread chart

You most likely have

M24×1.5 metric 24° cone (DIN)

A metric 24° cone fitting with an M24×1.5 thread. Parker’s table lists it only as 16S (heavy series, 16 mm tube).

Available on Amazon

Thread pitch gauge, SAE and metric

Measure the outside diameter of the tube too: the M24×1.5 thread alone doesn’t tell a light-series fitting from a heavy one.
French metric (“GAZ”) fittings also have a 24° seat: if the M24×1.5 part doesn’t match DIN, have a hydraulic hose shop check it.

Metric threads are named by their outside diameter and pitch: M24x1.5 is 24 mm across with 1.5 mm between threads.

Next

Hydraulic thread chart

You most likely have

M26×1.5 metric 24° cone (DIN)

A metric 24° cone fitting with an M26×1.5 thread. Parker’s table lists it only as 18L (light series, 18 mm tube).

Available on Amazon

Thread pitch gauge, SAE and metric

Measure the outside diameter of the tube too: the M26×1.5 thread alone doesn’t tell a light-series fitting from a heavy one.
French metric (“GAZ”) fittings also have a 24° seat: if the M26×1.5 part doesn’t match DIN, have a hydraulic hose shop check it.

Metric threads are named by their outside diameter and pitch: M26x1.5 is 26 mm across with 1.5 mm between threads.

Next

Hydraulic thread chart

You most likely have

M30×2 metric 24° cone (DIN)

A metric 24° cone fitting with an M30×2 thread. This thread is on two sizes: 22L (light series, 22 mm tube) and 20S (heavy series, 20 mm tube).

Available on Amazon

Thread pitch gauge, SAE and metric

Measure the outside diameter of the tube too: the M30×2 thread alone doesn’t tell a light-series fitting from a heavy one.
French metric (“GAZ”) fittings also have a 24° seat: if the M30×2 part doesn’t match DIN, have a hydraulic hose shop check it.

Metric threads are named by their outside diameter and pitch: M30x2 is 30 mm across with 2 mm between threads.

Next

Hydraulic thread chart

You most likely have

M36×2 metric 24° cone (DIN)

A metric 24° cone fitting with an M36×2 thread. This thread is on two sizes: 28L (light series, 28 mm tube) and 25S (heavy series, 25 mm tube).

Available on Amazon

Thread pitch gauge, SAE and metric

Measure the outside diameter of the tube too: the M36×2 thread alone doesn’t tell a light-series fitting from a heavy one.
French metric (“GAZ”) fittings also have a 24° seat: if the M36×2 part doesn’t match DIN, have a hydraulic hose shop check it.

Metric threads are named by their outside diameter and pitch: M36x2 is 36 mm across with 2 mm between threads.

Next

Hydraulic thread chart

You most likely have

M42×2 metric 24° cone (DIN)

A metric 24° cone fitting with an M42×2 thread. Parker’s table lists it only as 30S (heavy series, 30 mm tube).

Available on Amazon

Thread pitch gauge, SAE and metric

Measure the outside diameter of the tube too: the M42×2 thread alone doesn’t tell a light-series fitting from a heavy one.
French metric (“GAZ”) fittings also have a 24° seat: if the M42×2 part doesn’t match DIN, have a hydraulic hose shop check it.

Metric threads are named by their outside diameter and pitch: M42x2 is 42 mm across with 2 mm between threads.

Next

Hydraulic thread chart

You most likely have

M45×2 metric 24° cone (DIN)

A metric 24° cone fitting with an M45×2 thread. Parker’s table lists it only as 35L (light series, 35 mm tube).

Available on Amazon

Thread pitch gauge, SAE and metric

Measure the outside diameter of the tube too: the M45×2 thread alone doesn’t tell a light-series fitting from a heavy one.
French metric (“GAZ”) fittings also have a 24° seat: if the M45×2 part doesn’t match DIN, have a hydraulic hose shop check it.

Metric threads are named by their outside diameter and pitch: M45x2 is 45 mm across with 2 mm between threads.

Next

Hydraulic thread chart

You most likely have

M52×2 metric 24° cone (DIN)

A metric 24° cone fitting with an M52×2 thread. This thread is on two sizes: 42L (light series, 42 mm tube) and 38S (heavy series, 38 mm tube).

Available on Amazon

Thread pitch gauge, SAE and metric

Measure the outside diameter of the tube too: the M52×2 thread alone doesn’t tell a light-series fitting from a heavy one.
French metric (“GAZ”) fittings also have a 24° seat: if the M52×2 part doesn’t match DIN, have a hydraulic hose shop check it.

Metric threads are named by their outside diameter and pitch: M52x2 is 52 mm across with 2 mm between threads.

Next

Hydraulic thread chart

You most likely have

JIS 30° or a BSP cone, BSPP thread

A 30° seat with a British parallel thread. JIS fittings use this, and so do BSP 60° cone fittings (BS 5200, Parker K4).

Available on Amazon

Thread pitch gauge, SAE and metric

JIS and BS 5200 cones share the thread and seat angle but not every dimension, so they can’t be swapped. All Parker JIS fittings are stamped “JIS”.
Measure the thread to get the size: see the BSPP rows in the thread chart, or take the part to a hose shop.

A 30° seat and a 60° cone are the same angle measured two ways: 30° on each side.

Next

NPT vs BSP on hydraulics Hydraulic thread chart

You most likely have

JIS 30° metric, or Komatsu style

A 30° seat with a metric thread. JIS fittings and Komatsu-style flare fittings both use it, and at M14, M18 and M22 their threads are the same.

Available on Amazon

Hydraulic seat angle gauge

Don’t mix it up with a JIC 37° fitting: the seat angle and the metric thread are both different.
Check the machine’s parts list, or take the part to a hose shop to match it.

JIS metric threads include M14×1.5, M18×1.5 and M22×1.5. Komatsu style uses a 1.5 mm pitch from M14 to M42.

Next

Hydraulic thread chart

You most likely have

NPTF or NPSM 30° seat

An inch pipe thread with a 30° seat, forming a 60° cone. Hose ends like this are most often seen on machines of US origin.

Available on Amazon

Thread pitch gauge, SAE and metric

An NPTF male mates with an NPTF, NPSF or NPSM female.
Don’t confuse it with BSPT: BSP threads are cut at 55° and NPT at 60°, and most sizes have a different count.

To be sure of an NPSM or NPTF end, have a hydraulic hose shop match it.

Next

NPT vs BSP on hydraulics Hydraulic thread chart

You most likely have

-4 SAE 45° flare, 7/16-20

A -4 45° flare fitting for 1/4" tube, with a straight 7/16-20 thread.

Available on Amazon

Hydraulic seat angle gauge

A -4 JIC 37° fitting has the same 7/16-20 thread, so check the seat again with a 37°/45° gauge: the two don’t seal on each other.
A -4 45° male mates only with a 45° female or a dual-seat 37°/45° female.

Across the 7/16-20 threads: male about 11.1 mm (.437"), female about 9.9 mm.

Next

JIC vs ORB vs ORFS Hydraulic thread chart

You most likely have

-5 SAE 45° flare, 1/2-20

A -5 45° flare fitting for 5/16" tube, with a straight 1/2-20 thread.

Available on Amazon

Hydraulic seat angle gauge

A -5 JIC 37° fitting has the same 1/2-20 thread, so check the seat again with a 37°/45° gauge: the two don’t seal on each other.
A -5 45° male mates only with a 45° female or a dual-seat 37°/45° female.

Across the 1/2-20 threads: male about 12.7 mm (.500"), female about 11.5 mm.

Next

JIC vs ORB vs ORFS Hydraulic thread chart

You most likely have

-6 SAE 45° flare, 5/8-18

A -6 45° flare fitting for 3/8" tube, with a straight 5/8-18 thread.

Available on Amazon

Hydraulic seat angle gauge

At -6 the 45° thread differs from JIC (9/16-18), so a JIC part won’t thread on.
A -6 45° male mates only with a 45° female or a dual-seat 37°/45° female.

Across the 5/8-18 threads: male about 15.9 mm (.626"), female about 14.3 mm.

Next

JIC vs ORB vs ORFS Hydraulic thread chart

You most likely have

-8 SAE 45° flare, 3/4-16

A -8 45° flare fitting for 1/2" tube, with a straight 3/4-16 thread.

Available on Amazon

Hydraulic seat angle gauge

A -8 JIC 37° fitting has the same 3/4-16 thread, so check the seat again with a 37°/45° gauge: the two don’t seal on each other.
A -8 45° male mates only with a 45° female or a dual-seat 37°/45° female.

Across the 3/4-16 threads: male about 19.1 mm (.752"), female about 17.5 mm.

Next

JIC vs ORB vs ORFS Hydraulic thread chart

You most likely have

-10 SAE 45° flare, 7/8-14

A -10 45° flare fitting for 5/8" tube, with a straight 7/8-14 thread.

Available on Amazon

Hydraulic seat angle gauge

A -10 JIC 37° fitting has the same 7/8-14 thread, so check the seat again with a 37°/45° gauge: the two don’t seal on each other.
A -10 45° male mates only with a 45° female or a dual-seat 37°/45° female.

Across the 7/8-14 threads: male about 22.2 mm (.874"), female about 20.6 mm.

Next

JIC vs ORB vs ORFS Hydraulic thread chart

You most likely have

-12 SAE 45° flare, 1 1/16-14

A -12 45° flare fitting for 3/4" tube, with a straight 1 1/16-14 thread.

Available on Amazon

Hydraulic seat angle gauge

At -12 the 45° thread differs from JIC (1 1/16-12), so a JIC part won’t thread on.
A -12 45° male mates only with a 45° female or a dual-seat 37°/45° female.

Across the 1 1/16-14 threads: male about 27.0 mm (1.063"), female about 25.0 mm.

Next

JIC vs ORB vs ORFS Hydraulic thread chart

You most likely have

-4 JIC 37°, 7/16-20

A -4 37° flare fitting for 1/4" tube, with a straight 7/16-20 thread, sealing metal to metal on its cone.

Available on Amazon

Hydraulic seat angle gauge

A -4 SAE 45° fitting has the same 7/16-20 thread; only a seat gauge tells them apart, and the two don’t seal on each other.
A -4 ORB male has the same thread with an O-ring in place of the cone, and goes in a port.

Across the 7/16-20 threads: male about 11.1 mm (.437"), female about 10.0 mm.

Next

Adapters for a -4 JIC hose end JIC vs ORB vs ORFS Hydraulic thread chart

You most likely have

-5 JIC 37°, 1/2-20

A -5 37° flare fitting for 5/16" tube, with a straight 1/2-20 thread, sealing metal to metal on its cone.

Available on Amazon

Hydraulic seat angle gauge

A -5 SAE 45° fitting has the same 1/2-20 thread; only a seat gauge tells them apart, and the two don’t seal on each other.
A -5 ORB male has the same thread with an O-ring in place of the cone, and goes in a port.

Across the 1/2-20 threads: male about 12.7 mm (.500"), female about 11.6 mm.

Next

Adapters for a -5 JIC hose end JIC vs ORB vs ORFS Hydraulic thread chart

You most likely have

-6 JIC 37°, 9/16-18

A -6 37° flare fitting for 3/8" tube, with a straight 9/16-18 thread, sealing metal to metal on its cone.

A -6 ORB male has the same thread with an O-ring in place of the cone, and goes in a port.
A -4 ORFS fitting also has a 9/16-18 thread, with a flat face and an O-ring in place of the cone.

Across the 9/16-18 threads: male about 14.3 mm (.563"), female about 13.0 mm.

Next

Adapters for a -6 JIC hose end JIC vs ORB vs ORFS Hydraulic thread chart

You most likely have

-8 JIC 37°, 3/4-16

A -8 37° flare fitting for 1/2" tube, with a straight 3/4-16 thread, sealing metal to metal on its cone.

Available on Amazon

Hydraulic seat angle gauge

A -8 SAE 45° fitting has the same 3/4-16 thread; only a seat gauge tells them apart, and the two don’t seal on each other.
A -8 ORB male has the same thread with an O-ring in place of the cone, and goes in a port.

Across the 3/4-16 threads: male about 19.1 mm (.752"), female about 17.6 mm.

Next

Adapters for a -8 JIC hose end JIC vs ORB vs ORFS Hydraulic thread chart

You most likely have

-10 JIC 37°, 7/8-14

A -10 37° flare fitting for 5/8" tube, with a straight 7/8-14 thread, sealing metal to metal on its cone.

Available on Amazon

Hydraulic seat angle gauge

A -10 SAE 45° fitting has the same 7/8-14 thread; only a seat gauge tells them apart, and the two don’t seal on each other.
A -10 ORB male has the same thread with an O-ring in place of the cone, and goes in a port.

Across the 7/8-14 threads: male about 22.2 mm (.874"), female about 20.5 mm.

Next

Adapters for a -10 JIC hose end JIC vs ORB vs ORFS Hydraulic thread chart

You most likely have

-12 JIC 37°, 1 1/16-12

A -12 37° flare fitting for 3/4" tube, with a straight 1 1/16-12 thread, sealing metal to metal on its cone.

A -12 ORB male has the same thread with an O-ring in place of the cone, and goes in a port.

Across the 1 1/16-12 threads: male about 27.0 mm (1.063"), female about 24.6 mm.

Next

Adapters for a -12 JIC hose end JIC vs ORB vs ORFS Hydraulic thread chart

You most likely have

-14 JIC 37°, 1 3/16-12

A -14 37° flare fitting for 7/8" tube, with a straight 1 3/16-12 thread, sealing metal to metal on its cone.

A -14 ORB male has the same thread with an O-ring in place of the cone, and goes in a port.
A -12 ORFS fitting also has a 1 3/16-12 thread, with a flat face and an O-ring in place of the cone.

Across the 1 3/16-12 threads: male about 30.1 mm (1.185"), female about 28.3 mm.

Next

JIC vs ORB vs ORFS Hydraulic thread chart

You most likely have

-16 JIC 37°, 1 5/16-12

A -16 37° flare fitting for 1" tube, with a straight 1 5/16-12 thread, sealing metal to metal on its cone.

A -16 ORB male has the same thread with an O-ring in place of the cone, and goes in a port.

Across the 1 5/16-12 threads: male about 33.3 mm (1.311"), female about 31.3 mm.

Next

Adapters for a -16 JIC hose end JIC vs ORB vs ORFS Hydraulic thread chart

You most likely have

-20 JIC 37°, 1 5/8-12

A -20 37° flare fitting for 1 1/4" tube, with a straight 1 5/8-12 thread, sealing metal to metal on its cone.

A -20 ORB male has the same thread with an O-ring in place of the cone, and goes in a port.

Across the 1 5/8-12 threads: male about 41.3 mm (1.626"), female about 39.2 mm.

Next

JIC vs ORB vs ORFS Hydraulic thread chart

You most likely have

-24 JIC 37°, 1 7/8-12

A -24 37° flare fitting for 1 1/2" tube, with a straight 1 7/8-12 thread, sealing metal to metal on its cone.

A -24 ORB male has the same thread with an O-ring in place of the cone, and goes in a port.

Across the 1 7/8-12 threads: male about 47.6 mm (1.874"), female about 45.6 mm.

Next

JIC vs ORB vs ORFS Hydraulic thread chart

As an Amazon Associate, What Adapter For earns from qualifying purchases.

How to identify a hydraulic fitting

Hydraulic threads look alike, so they have to be measured and compared with thread tables, in five steps:

Tapered or straight? With a caliper, measure across the first, fourth and last full threads. If the width changes, the thread is tapered, like NPT or BSPT. If it doesn’t, the thread is straight.
Measure the width. Measure the outside of a male thread or the inside of a female one, crest to crest. On a tapered thread use the fourth or fifth full thread. Don’t expect an exact match with the table: threads are made to tolerances.
Find the pitch. Try pitch gauges on the threads until one matches: threads per inch for inch and British threads, millimeters between threads for metric. Holding the gauge and the threads up against a light helps.
Look up the thread. Male or female, tapered or straight, the width and the pitch together name the thread. The hydraulic thread chart lists them by size.
Identify the end. Look at how it seals: only the threads, a cone or seat, an O-ring behind the threads, or an O-ring in a flat face. On a cone or seat, a seat gauge gives the angle.

The tools

Caliper: for the width across the threads, read at the largest point.
Pitch gauges: an inch (US) gauge, and a metric and British one. Many hydraulic threads differ by only one thread per inch, so try both.
Seat gauges: 37°, 45° and 30°. Hold one on the seat: when its centerline points straight out along the fitting, the angles match. If it sits at an angle, try another.
A hose shop: if you can’t settle it, a hydraulic hose shop can match the part with the one it replaces.

Fittings that look alike

-6 JIC, -6 ORB and -4 ORFS all have a 9/16-18 thread. The end tells them apart: a cone on the nose, an O-ring behind the threads, or an O-ring in a flat face.
JIC 37° and SAE 45° share the thread at -2, -3, -4, -5, -8 and -10. They don’t seal on each other, and only a seat gauge separates them.
1/2" and 3/4" NPT and BSPT both have 14 threads per inch and nearly the same width. Telling them apart may take an optical comparator, so look for markings or the machine’s parts list.
Other NPT and BSP sizes are one thread per inch or less apart (27 and 28, 18 and 19, 11.5 and 11). Check with both an inch and a British gauge.
NPT and NPTF have the same sizes and thread count, so the tool answers NPT/NPTF.
Metric 24° cones: one thread can be a light-series or a heavy-series fitting, so measure the tube’s outside diameter as well as the thread. French metric (GAZ) fittings also have a 24° seat.
30° seats: JIS and Komatsu-style fittings share the M14, M18 and M22 threads. A JIS fitting with a BSP thread and a BS 5200 60° cone look alike but can’t be interchanged.

Before you loosen a fitting

Turn the machine off, put the equipment in a safe, neutral position and release the pressure before you loosen anything. Turning off the pump may not release it: check valves can hold pressure in a hose, and it can take minutes or hours to bleed away.
Never feel for a leak with your hand or any other part of your body. Oil under pressure can go through skin, and a pinhole leak can be almost invisible.
If oil gets under your skin, get medical help at once, even if it doesn’t hurt. An injection injury can lead to amputation.
Threads that screw together don’t prove the parts match. Some parts that don’t belong together still thread on, and then leak or come apart under pressure.
Use only fittings whose published working pressure is at or above your machine’s maximum pressure. If a fitting has no published rating, don’t use it.
Stay clear the first time you run the machine under pressure after a repair.

Common questions

How do I tell a JIC fitting from an ORB fitting?

Look at the male end. A JIC has a 37° cone on its nose and seals on it; an ORB has an O-ring at the base of its threads and screws into a port. The thread is the same at every size, so measuring alone won't separate them.

Can I identify a hydraulic fitting without tools?

Not reliably. Many threads look alike and some differ by one thread per inch, so you need a caliper and pitch gauges, and a seat gauge for flare fittings. A hydraulic hose shop can match the part instead.

Why doesn't my measurement match the chart exactly?

Threads are made to tolerances, so a real part measures a little differently from the table. Pick the closest size that also matches the thread count and the seal.

Where we get our information from

The steps come from Swagelok’s thread identification guide, the thread tables from Swagelok and Parker, the tools from Parker and Gates, and the safety lines from Parker’s and Gates’ safety guides and the UK Health and Safety Executive. Checked against published data from Parker Hannifin, Gates, UK Health and Safety Executive and Swagelok.

See all 8 sources

Swagelok, Thread and End Connection Identification Guide (MS-13-77)
Parker Hannifin, Catalog 4400, Hose, Fittings, and Equipment (October 9, 2026), Hydraulic Technical Section pp. 456-473: identifying fitting types and sealing methods, measuring threads with a gauge and caliper, thread tables for NPTF, JIC 37°, SAE 45°, O-ring boss, ORFS, BSPP, BSPT, metric DIN 24° and JIS 30°; hose dash sizes (p. 6)
Parker Hannifin, Catalog 4300, Tube Fittings (PDF Version 13, 8/2026): straight thread, pipe thread and BSPP adapters and their part numbers (pp. A14-A15, B15-B19, E15, E17), port connection guidelines (p. E5), JIS fittings (p. G3), K4 vs JIS 60° cones (p. H4), Komatsu style 30° flare (p. I3), brass Triple-Lok ratings (pp. B7, B15)
Gates, Safe Hydraulics Pocket Guide: tools for coupling identification, inspection steps (turn off and lock out the power, put the equipment in a safe and/or neutral position), components that thread together but aren't compatible
Parker Hannifin, Parker Safety Guide for Selecting and Using Hose, Tubing, Fittings, Connectors, Conductors, Valves and Related Accessories, Publication 4400-B.1, revision B (8-NOV-2024), in Catalog 4400 pp. 495-498: published maximum working pressure at or above the system's (2.2), never feel for a leak, pressure that stays after shutdown, injection injuries (5.6)
Gates, Hydraulic Hoses & Couplings Product & Application Guide (2024): avoid fluid injection injuries, get medical help at once even if no pain is felt, stay out of hazardous areas while testing under pressure
UK Health and Safety Executive, High pressure fluid injection hazards (agriculture, machinery): injection injuries, operator errors such as searching for leaks with bare hands and failing to release pressure
UK Health and Safety Executive, Safety alert: Hydraulic injection injury: injuries at low pressures, prompt medical treatment, replacement fittings matched to the original equipment maker's specification

General guidance from fitting makers' catalogs and safety guides, not a substitute for your machine's manual. Release the pressure before you loosen any fitting, use only parts rated for your machine's pressure, and if you can't identify a fitting for sure, take it to a hydraulic hose shop.