How to Identify and Measure Fittings
Pipe size is an industry designation, not the actual size. View information about how to measure threaded and unthreaded pipe and pipe fittings.
More
Open-Flow Quick-Disconnect Hose Couplings for Air and Water
Couplings allow for maximum flow because there’s no shut-off valve in the plug or the socket. A complete coupling consists of a plug and a socket (both sold separately) that connect and disconnect quickly. Use them if you need frequent access to a line. All Open-Flow plugs are compatible with any of the Open-Flow sockets of the same coupling size, regardless of the pipe size. They are compatible with Hansen ST, Parker ST, and Perfecting E couplings.
Plugs are also known as nipples.
Sockets are sleeve-lock style. To connect, slide back the sleeve on the socket, insert the plug, and release the sleeve. To disconnect, slide back the sleeve and pull out the plug.
Plugs and sockets with a clamp-on barbed end insert into rubber hose and secure with a clamp.
Brass plugs and sockets are softer than other metal plugs and sockets, so they’re easier to thread together. They have good corrosion resistance. 303 stainless steel plugs and sockets have very good corrosion resistance. They’re the best choice for high-humidity environments.
Note: To ensure a correct fit, make sure that the plug and socket have the same coupling size.
Warning: There is no valve in these couplings. Stop the air and water flow before you disconnect the line.
For technical drawings and 3-D models, click on a part number.
- Maximum Pressure: See table
- Temperature Range: -40° to 250° F
- Compatible With: Hansen ST Couplings, Parker ST Couplings, Perfecting E Couplings
Plug Tip | ||||||
|---|---|---|---|---|---|---|
| Coupling Size | Lg. | Dia. | For Hose ID | Max. Pressure | Each | |
303 Stainless Steel  | ||||||
| 1/2 | 1/8" | 5/8" | 1/2" | 3,600 psi @ 72° F | 00000000 | 000000 |
Ring-Lock Quick-Disconnect Hose Couplings for Air
A complete coupling consists of a plug and a socket (both sold separately) that connect and disconnect quickly. Use them if you need frequent access to a line. All Ring-Lock plugs are compatible with any of the Ring-Lock sockets of the same coupling size, regardless of the pipe size. Plugs and sockets are zinc-plated steel, which is strong and durable. They have fair corrosion resistance, so they should be used primarily in dry environments.
Sockets have a shut-off valve that stops the flow when the coupling is separated, so air won’t leak from the line. They are push-to-connect style. To connect, push the plug into the socket until you hear a click. To disconnect, twist the sleeve on the socket and pull out the plug. This twist-to-disconnect feature reduces the chance of accidental disconnection.
Note: To ensure a correct fit, make sure that the plug and socket have the same coupling size.
For technical drawings and 3-D models, click on a part number.
- Maximum Pressure: 300 psi @ 72° F
- Temperature Range: -40° to 225° F
For Plug Tip | ||||||
|---|---|---|---|---|---|---|
| Coupling Size | Lg. | Dia. | Pipe Size | Thread Type | Each | |
Zinc-Plated Steel | ||||||
| 3/8 | 5/16" | 7/16" | 1/4 | NPT | 0000000 | 000000 |
Screw-On Hose Fittings for Air and Water
The female connector screws directly onto rubber hose without the need for a separate adapter. You’ll need a female connector (ferrule) and a male adapter (stem) with the same hose ID to make a connection. Screw the female connector onto hose, then thread the male adapter into the female connector. When assembled, the fitting compresses against the hose, forming a strong seal. Also known as reusable fittings, they can be unscrewed from the hose end and used on a new hose.
Brass fittings are softer than 303 stainless steel fittings, so they’re easier to thread together. They have good corrosion resistance.
NPTF (Dryseal) threads are compatible with NPT threads.
For technical drawings and 3-D models, click on a part number.
- Maximum Pressure: 250 psi @ 72° F
- Temperature Range: -40° to 160° F
| For Hose ID | Pipe Size | Thread Type | Pkg. Qty. | Pkg. | |
Brass | |||||
|---|---|---|---|---|---|
| 3/8" | 1/2 | NPTF | 2 | 0000000 | 000000 |
Push-to-Connect Tube Fittings for Air
- Temperature Range: 0° to 170° F, except polybutylene plastic fittings are 32° to 140° F
- Tubing: Use with firm (Durometer 95A-45D) polyethylene plastic or polyurethane rubber
- Specifications Met: ISO 14743, except cartridges and polybutylene plastic fittings
Insert tubing into these fittings and an internal gripping ring and O-ring hold the tubing tight. They are also known as instant fittings. To disconnect, push on the release ring and pull the tubing out of the fitting. Fittings have good corrosion resistance. Use them in low-pressure applications.
Identification rings (sold separately) snap over the release ring so you can color-code your lines.
Clips (sold separately) align and organize your tubing and fittings.
For technical drawings and 3-D models, click on a part number.
Nickel-Plated Brass Push-to-Connect Tube Fittings for Air
- For Use With: Air, Lubricated Air
- Temperature Range: 0° to 140° F
- Tubing: Fittings with Release Ring and Fittings with no Release Type: Use with firm or hard (Durometer 95A-60D) nylon plastic, polyethylene plastic or polyurethane rubber
Fittings with Release Sleeve: Use with firm or hard (Durometer 95A-60D) polyethylene plastic or polyurethane rubber
Made of nickel-plated brass, these fittings have better corrosion resistance than unplated brass fittings. Also known as instant fittings, they connect to tubing with a push, and an internal gripping ring and O-ring hold the tubing tight. To disconnect, push on the release ring or sleeve and pull the tubing out of the fitting.
Fittings with release sleeve are easier to disconnect than fittings with a release ring because they are seamless and won't collect dirt and debris.
For technical drawings and 3-D models, click on a part number.
Release Sleeve | ||||
|---|---|---|---|---|
| For Tube OD | Material | Max. Pressure | Each | |
| 1/2" | Nickel-Plated Brass | 230 psi @ 72° F | 00000000 | 000000 |
Rotating Push-to-Connect Tube Fittings for Air
- Temperature Range: 25° to 140° F
- Tubing: Use with firm or hard (Durometer 55D-60D, Durometer 91A-97A, or Rockwell R70-R85) nylon plastic or polyurethane rubber
Ball bearings allow these fittings to rotate 360°, even after they are tightened. Fittings rotate at the pipe end and have a special seal that reduces friction to allow for continuous rotation. Also known as instant fittings, they connect to tubing with a push, and an internal gripping ring and O-ring hold the tubing tight. To disconnect, push on the release ring and pull the tubing out of the fitting. They have good corrosion resistance.
Fittings with PTFE thread sealant offer extra protection against leaks.
For technical drawings and 3-D models, click on a part number.
| For Tube OD | Pipe Size | Bearing Construction | Tube Connection Material | Pipe Connection Material | Color | Release Ring Color | Max. Pressure | Features | Each | |
NPT Threads | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| 3/8" | 3/8 | Single Row | Polybutylene Plastic | Nickel-Plated Brass | Gray | Red | 140 psi @ 72° F | PTFE Thread Sealant | 000000000 | 000000 |
Yor-Lok Fittings for Stainless Steel Tubing
A nut with two sleeves (ferrules) gives these fittings extra gripping power. The sleeves bite into tubing as you tighten the nut, creating a strong seal. Also known as instrumentation fittings, they are made to tight tolerances for use in high-precision applications. They are compatible with Swagelok®, Let-Lok, and A-Lok fittings.
316 stainless steel fittings have excellent corrosion resistance.
For technical drawings and 3-D models, click on a part number.
- For Use With: Air, Cutting Oil, Fuel Oil, Gasoline, Hydraulic Fluid, Mineral Oil, Natural Gas, Steam, Water
- Tubing: Use with welded or seamless 304/304L or 316/316L stainless steel that meets ASTM A213, ASTM A249, or ASTM A269
Through-wall fittings are also known as bulkhead couplings and panel-mount couplings; they mount through your wall or panel to create an inlet or outlet.
For Tube | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| OD | Wall Thick. | Pipe Size | Material | Max. Pressure | Temp. Range, °F | For Hole Dia. | For Max. Wall Thick. | Each | |
NPT Threads | |||||||||
| 3/8" | 0.035" to 0.065" | 1/4 | 316 Stainless Steel | 2,500 psi @ 72° F | -420° to 1200° | 9/16" | 9/16" | 00000000 | 000000 |
For Tube | ||||||
|---|---|---|---|---|---|---|
| OD | Wall Thick. | Nut Material | Max. Pressure | Temp. Range, °F | Each | |
| 3/8" | 0.035" | 316 Stainless Steel | 2,500 psi @ 72° F | -420° to 1200° | 00000000 | 00000 |
For Tube | ||||||
|---|---|---|---|---|---|---|
| OD | Wall Thick. | Sleeve Material | Max. Pressure | Temp. Range, °F | Each | |
| 3/8" | 0.035" | 316 Stainless Steel | 2,500 psi @ 72° F | -420° to 1200° | 00000000 | 00000 |
PTFE sleeves are plastic instead of stainless steel, so they won’t damage tubing.
| For Tube OD | Sleeve Material | Max. Pressure | Temp. Range, °F | Each | |
| 3/8" | PTFE Plastic | Not Rated | -65° to 350° | 00000000 | 00000 |
Quick-Clamp High-Vacuum Fittings for Stainless Steel Tubing
- For Use With:
Fittings with Gasket End: Air, Argon, Helium, Nitrogen
All Other Fittings: Air - Specifications Met: ISO 2861
Instead of a gasket, these fittings have a metal-reinforced O-ring that is designed for high-vacuum applications, such as vacuum coating and heat treating, leak testing, and analyzing gases. Also known as KF, QF, and NW fittings, they are the most common type of connection in high-vacuum systems. Connect with a clamp and another quick-clamp fitting for fast, easy access to your line. To use fittings in pressure applications, use a pressure-rated ring (sold separately). Made of 304 stainless steel, these fittings have very good corrosion resistance.
Note: To complete a connection, you’ll need two quick-clamp fittings, a ring, and a clamp (all sold separately).
For technical drawings and 3-D models, click on a part number.
- Temperature Range: 0° to 300° F
- Tubing: Use with 304/304L or 316/316L stainless steel
Fittings with barbed hose end connect flexible hose or tubing to your system. Secure with a hose clamp (sold separately).
| For Tube OD | Flange OD | High-Vacuum Flange Size | High Vacuum Connection Type | For Hose ID | Material | Max. Vacuum | Each | |
| 2" | 2.95" | 50 | ISO-KF | 2" | 304 Stainless Steel | 1 × 10 -7 torr @ 72° F | 00000000 | 000000 |
- Temperature Range: 0° to 300° F
- Tubing: Use with 304/304L stainless steel, 316/316L stainless steel, or aluminum
Clamps tighten by hand.
Lever clamps are also known as toggle clamps.
Clamps with lanyard let you secure the clamp to equipment.
| For Tube OD | For Flange OD | For High-Vacuum Flange Size | High Vacuum Connection Type | Material | Max. Vacuum | Lanyard Lg. | Each | |
Wing Nut | ||||||||
|---|---|---|---|---|---|---|---|---|
| 2" | 2.95" | 50 | ISO-KF | Aluminum | 1 × 10 -7 torr @ 72° F | __ | 0000000 | 000000 |
Lever | ||||||||
| 2" | 2.95" | 50 | ISO-KF | Aluminum | 1 × 10 -7 torr @ 72° F | __ | 0000000 | 00000 |
Lever with Lanyard | ||||||||
| 2" | 2.95" | 50 | ISO-KF | Aluminum | 1 × 10 -7 torr @ 72° F | 5 3/4" | 00000000 | 00000 |
- Temperature Range:
Fittings with Fluoroelastomer O-Ring: 0° to 300° F
Fittings with Silicone O-Ring: -50° to 390°F - Tubing: Use with 304/304L stainless steel, 316/316L stainless steel, or aluminum
Use these rings with quick-clamp high-vacuum fittings. They consist of a stainless steel inner ring covered by an O-ring.
Silicone rings withstand higher temperatures than fluoroelastomer ones.
| For Tube OD | For Flange OD | For High-Vacuum Flange Size | High Vacuum Connection Type | Inner Ring Material | Max. Vacuum | Max. Pressure | Each | |
Fluoroelastomer Rubber O-Ring | ||||||||
|---|---|---|---|---|---|---|---|---|
Rings | ||||||||
| 2" | 2.95" | 50 | ISO-KF | 304 Stainless Steel | 1 × 10 -7 torr @ 72° F | Not Rated | 0000000 | 000000 |
Rings with Stainless Steel Screen | ||||||||
| 2" | 2.95" | 50 | ISO-KF | 304 Stainless Steel | 1 × 10 -7 torr @ 72° F | Not Rated | 00000000 | 00000 |
Rings with Aluminum Outer Ring | ||||||||
| 2" | 2.95" | 50 | ISO-KF | 304 Stainless Steel | 1 × 10 -7 torr @ 72° F | 50 psi @ 72° F | 0000000 | 00000 |
Silicone Rubber O-Ring | ||||||||
Rings | ||||||||
| 2" | 2.95" | 50 | ISO-KF | 304 Stainless Steel | 1 × 10 -7 torr @ 72° F | Not Rated | 00000000 | 00000 |
- Temperature Range: 0° to 300° F
- Tubing: Use with 304/304L stainless steel, 316/316L stainless steel, or aluminum
Hose absorbs moderate vibration
| For Tube OD | Flange OD | High-Vacuum Flange Size | High Vacuum Connection Type | Material | Max. Vacuum | Bend Radius | Flexibility | Each | |
4 3/16" Lg. | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| 2" | 2.95" | 50 | ISO-KF | 304 Stainless Steel | 1 × 10 -7 torr @ 72° F | __ | Flexible | 0000000 | 0000000 |
12" Lg. | |||||||||
| 2" | 2.95" | 50 | ISO-KF | 304 Stainless Steel | 1 × 10 -7 torr @ 72° F | 3 1/4" | Flexible | 00000000 | 000000 |
24" Lg. | |||||||||
| 2" | 2.95" | 50 | ISO-KF | 304 Stainless Steel | 1 × 10 -7 torr @ 72° F | 3 1/4" | Flexible | 00000000 | 000000 |
39" Lg. | |||||||||
| 2" | 2.95" | 50 | ISO-KF | 304 Stainless Steel | 1 × 10 -7 torr @ 72° F | 3 1/4" | Flexible | 00000000 | 000000 |
- Temperature Range: 0° to 190° F
- Tubing: Use with 304/304L or 316/316L stainless steel
Valves are also known as vacuum isolation valves. They connect to a vacuum system so you can install gauges, release gases, and remove air. They operate manually and have a compact body that fits easily into tight spaces.
| Actuation | For Tube OD | Flange OD | High-Vacuum Flange Size | Max. Vacuum | Body Material | Overall Ht. | Overall Lg. | Each | |
| Manual | 2" | 2 15/16" | 50 | 10 -7 torr @ 72° F | 304 Stainless Steel | 8" | 4 1/2" | 00000000 | 0000000 |
Compression Fittings for Steel Tubing
- For Use With: Inch: Air, Hydraulic Fluid, Water
Metric: Hydraulic Fluid - Tubing: Inch: Use with welded steel
Metric: Use with seamless steel - Specifications Met: Inch: SAE J514
Metric: ISO 8434, DIN 2353
A single sleeve (ferrule) bites into tubing as you tighten the nut, creating a strong seal. The nut and sleeve are included. Fittings are also known as flareless and bite fittings.
Zinc-plated steel fittings have fair corrosion resistance.
NPTF (Dryseal) threads are compatible with NPT threads.
For technical drawings and 3-D models, click on a part number.
- Temperature Range: See table
For Tube | |||||||
|---|---|---|---|---|---|---|---|
| OD | Wall Thick. | Pipe Size | Material | Max. Pressure | Temp. Range, °F | Each | |
NPTF Threads | |||||||
| 1/2" | 0.049" | 1/2 | Zinc-Plated Steel | 2,000 psi @ 72° F | -65° to 400° | 000000000 | 00000 |
- Temperature Range: See table
| For Tube OD | Nut Material | Max. Pressure | Temp. Range, °F | Each | |
| 1/2" | Zinc-Plated Steel | 2,000 psi @ 72° F | -65° to 400° | 000000000 | 00000 |
- Temperature Range: See table
| For Tube OD | Sleeve Material | Max. Pressure | Temp. Range, °F | Each | |
| 1/2" | Zinc-Plated Steel | 2,000 psi @ 72° F | -65° to 400° | 000000000 | 00000 |
45° Flared Fittings for Copper and Brass Tubing
- Temperature Range: -65° to 250° F
- Tubing: Use with seamless brass and copper that meets ASTM B280
No sleeve is required to assemble these fittings, which makes for a faster, more convenient installation compared to 37° flared fittings. They require a nut (sold separately) for each tube end. Fittings are also known as refrigeration and SAE fittings. They are brass for good corrosion resistance.
NPTF (Dryseal) threads are compatible with NPT threads.
Copper tube size is the accepted designation of the copper tubing industry, not the actual tube OD.
For technical drawings and 3-D models, click on a part number.
- For Use With: Air, Cutting Oil, Diesel Fuel, Fuel Oil, Mineral Oil, Refrigerant, Water; except adapters for 1/8" and 1" tube OD are not for use with fuel oil
- Specifications Met: See table
- For Use With: Air, Cutting Oil, Diesel Fuel, Fuel Oil, Mineral Oil, Refrigerant, Water
- Specifications Met: See table
For Tube | Socket Connection | |||||||
|---|---|---|---|---|---|---|---|---|
| OD | Wall Thick. | Copper Tube Size | For Tube OD | Material | Max. Pressure | Specifications Met | Each | |
| 3/4" | 0.035" | 3/4 | 7/8" | Brass | 550 psi @ 72° F | SAE J512, SAE J513, UL Listed | 000000000 | 000000 |
- For Use With: Air, Cutting Oil, Diesel Fuel, Fuel Oil, Mineral Oil, Refrigerant, Water; except nuts for 1" tube OD are not for use with fuel oil
- Specifications Met: SAE J512, SAE J513, UL Listed; except nuts for 1" tube OD meet SAE J512 and SAE J513 only
Quick-Clamp High-Vacuum Fittings for Aluminum Tubing
- For Use With: Air
- Specifications Met: ISO 2861
For use in high-vacuum systems, these fittings use a metal reinforced O-ring to create an airtight seal. To form a complete connection, pair two adapters with a clamp and a ring (all sold separately). Made of aluminum, these fittings are lightweight and resist corrosion. This and the airtight seal make them a good choice for vacuum coating, heat treating, or leak testing. Also known as KF, QF, and NW fittings.
For technical drawings and 3-D models, click on a part number.
- Temperature Range: 0° to 300° F
- Tubing: Use with 304/304L stainless steel, 316/316L stainless steel, or aluminum
Connect quick-clamp fittings in high-vacuum applications. Clamps tighten by hand. They are aluminum, which is lightweight with good corrosion resistance.
Lever clamps are also known as toggle clamps.
Clamps with lanyard let you secure the clamp to equipment.
| For Tube OD | For Flange OD | For High-Vacuum Flange Size | High Vacuum Connection Type | Material | Max. Vacuum | Lanyard Lg. | Each | |
Wing Nut | ||||||||
|---|---|---|---|---|---|---|---|---|
| 1 1/2" | 2.16" | 40 | ISO-KF | Aluminum | 1 × 10 -7 torr @ 72° F | __ | 0000000 | 000000 |
| 2" | 2.95" | 50 | ISO-KF | Aluminum | 1 × 10 -7 torr @ 72° F | __ | 0000000 | 00000 |
Lever | ||||||||
| 1 1/2" | 2.16" | 40 | ISO-KF | Aluminum | 1 × 10 -7 torr @ 72° F | __ | 0000000 | 00000 |
| 2" | 2.95" | 50 | ISO-KF | Aluminum | 1 × 10 -7 torr @ 72° F | __ | 0000000 | 00000 |
Lever with Lanyard | ||||||||
| 1 1/2" | 2.16" | 40 | ISO-KF | Aluminum | 1 × 10 -7 torr @ 72° F | 5 3/4" | 00000000 | 00000 |
| 2" | 2.95" | 50 | ISO-KF | Aluminum | 1 × 10 -7 torr @ 72° F | 5 3/4" | 00000000 | 00000 |
- Temperature Range: 0° to 350° F
- Tubing: Use with aluminum
- Temperature Range: 0° to 300° F
- Tubing: Use with 304/304L stainless steel, 316/316L stainless steel, or aluminum
Hose absorbs moderate vibration.
| For Tube OD | Flange OD | High-Vacuum Flange Size | High Vacuum Connection Type | Material | Max. Vacuum | Bend Radius | Flexibility | Each | |
4 3/16" Lg. | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| 1 1/2" | 2.16" | 40 | ISO-KF | 304 Stainless Steel | 1 × 10 -7 torr @ 72° F | __ | Flexible | 0000000 | 0000000 |
| 2" | 2.95" | 50 | ISO-KF | 304 Stainless Steel | 1 × 10 -7 torr @ 72° F | __ | Flexible | 0000000 | 000000 |
12" Lg. | |||||||||
| 1 1/2" | 2.16" | 40 | ISO-KF | 304 Stainless Steel | 1 × 10 -7 torr @ 72° F | 2 1/2" | Flexible | 00000000 | 000000 |
| 2" | 2.95" | 50 | ISO-KF | 304 Stainless Steel | 1 × 10 -7 torr @ 72° F | 3 1/4" | Flexible | 00000000 | 000000 |
24" Lg. | |||||||||
| 1 1/2" | 2.16" | 40 | ISO-KF | 304 Stainless Steel | 1 × 10 -7 torr @ 72° F | 2 1/2" | Flexible | 00000000 | 000000 |
| 2" | 2.95" | 50 | ISO-KF | 304 Stainless Steel | 1 × 10 -7 torr @ 72° F | 3 1/4" | Flexible | 00000000 | 000000 |
39" Lg. | |||||||||
| 1 1/2" | 2.16" | 40 | ISO-KF | 304 Stainless Steel | 1 × 10 -7 torr @ 72° F | 2 1/2" | Flexible | 00000000 | 000000 |
| 2" | 2.95" | 50 | ISO-KF | 304 Stainless Steel | 1 × 10 -7 torr @ 72° F | 3 1/4" | Flexible | 00000000 | 000000 |
- Temperature Range: 0° to 190° F
Valves are also known as vacuum isolation valves. They connect to a vacuum system so you can install gauges, release gases, and remove air. They operate manually and have a compact body that fits easily into tight spaces.