How to Identify and Measure Fittings
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Brass Push-to-Connect Tube Fittings for Air
- Temperature Range: 0° to 200° F, except Tube Stem Straight Connectors are 0° to 150° F, and Plugs are 0° to 170° F
- Tubing: See table
These fittings offer good protection against corrosive environments. 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.
UN/UNF (SAE Straight) threads are also known as O-ring boss threads.
For technical drawings and 3-D models, click on a part number.
Release Ring | For Tube | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| For Tube OD | Thread Size  | Material | Material | Color | Max. Pressure | Material | Hardness Rating | Each | |
UN/UNF (SAE Straight) Threads | |||||||||
| 5/32" | 1/4"-28 | Nickel-Plated Brass | Plastic | Black | 290 psi @ 72° F | Nylon Plastic, Polyethylene Plastic | Hard | 000000000 | 00000 |
Release Ring | For Tube | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| For Tube OD | Thread Size | Material | Material | Color | Max. Pressure | Material | Hardness Rating | Each | |
UN/UNF (SAE Straight) Threads | |||||||||
| 5/32" | 1/4"-28 | Nickel-Plated Brass | Plastic | Black | 290 psi @ 72° F | Nylon Plastic, Polyethylene Plastic | Hard | 000000000 | 000000 |
Plugs insert into the push-to-connect end of another fitting.
| Tube Stem OD | Material | Max. Pressure | Specifications Met | Each | |
| 5/32" | Nylon Plastic | 290 psi @ 72° F | ISO 14743 | 00000000 | 00000 |
Tight-Seal Plastic Barbed Tube Fittings for Air and Water
Minimize leaks in your line—these fittings have a single barb that creates a smooth clamping surface for extra-tight connections. Fittings are nylon for excellent impact and abrasion resistance.
For technical drawings and 3-D models, click on a part number.
- Temperature Range: See table
- Tubing: Use with firm (Durometer 75A-80A) polyurethane rubber or PVC plastic
- Clarity: Black: Opaque; White: Opaque; Off-White: Semi-Clear
| For Tube ID | Thread Size | Material | Max. Pressure | Temp. Range, °F | Pkg. Qty. | Color | Pkg. | |
UNF Threads | ||||||||
|---|---|---|---|---|---|---|---|---|
| 1/16" | 1/4"-28 | Nylon Plastic | Not Rated | -50° to 275° | 10 | White | 00000000 | 00000 |
| 3/32" | 1/4"-28 | Nylon Plastic | Not Rated | -50° to 275° | 10 | White | 00000000 | 0000 |
| 1/8" | 1/4"-28 | Nylon Plastic | Not Rated | -50° to 275° | 10 | White | 00000000 | 0000 |
| 5/32" | 1/4"-28 | Nylon Plastic | Not Rated | -50° to 275° | 10 | White | 00000000 | 0000 |
| 3/16" | 1/4"-28 | Nylon Plastic | Not Rated | -50° to 275° | 10 | White | 00000000 | 0000 |
- Temperature Range: See table
- Tubing: Use with firm (Durometer 75A-80A) polyurethane rubber or PVC plastic
- Clarity: Black: Opaque; White: Opaque; Off-White: Semi-Clear
| For Tube ID | Thread Size | Material | Max. Pressure | Temp. Range, °F | Pkg. Qty. | Color | Pkg. | |
UNF Threads | ||||||||
|---|---|---|---|---|---|---|---|---|
| 1/8" | 1/4"-28 | Nylon Plastic | Not Rated | -50° to 275° | 10 | White | 00000000 | 000000 |
Tight-Seal Moisture-Resistant Plastic Barbed Tube Fittings for Air and Water
- Temperature Range: -20° to 280° F
- Tubing: Use with firm or soft (Durometer 50A-90A) polyurethane rubber or PVC plastic
- Specifications Met: FDA Compliant 21 CFR 177.2470
Fittings have a single barb that creates a smooth clamping surface for extra-tight connections that minimize leaks. Made of acetal, they won’t absorb water and lose strength, even in high-humidity environments.
For technical drawings and 3-D models, click on a part number.
| For Tube ID | Thread Size | Material | Color | Clarity | Max. Pressure | Each | |
UNF Threads | |||||||
|---|---|---|---|---|---|---|---|
| 1/16" | 1/4"-28 | Acetal Plastic | White | Semi-Clear | Not Rated | 00000000 | 00000 |
| 3/32" | 1/4"-28 | Acetal Plastic | White | Semi-Clear | Not Rated | 00000000 | 000 |
| 1/8" | 1/4"-28 | Acetal Plastic | White | Semi-Clear | Not Rated | 00000000 | 0000 |
| 5/32" | 1/4"-28 | Acetal Plastic | White | Semi-Clear | Not Rated | 00000000 | 0000 |
| 3/16" | 1/4"-28 | Acetal Plastic | White | Semi-Clear | Not Rated | 00000000 | 0000 |
Aluminum Low-Pressure Barbed Tube Fittings for Air and Water
- For Use With: Air, Lubricated Air, Water
- Temperature Range: -40° to 230° F
- Tubing: Use with hard (Durometer 75A-60D) EVA plastic, polyethylene plastic, polyurethane rubber or PVDF plastic
Made of aluminum, these fittings are lighter in weight than other metal barbed tube fittings and have good corrosion resistance. The barb grips onto tubing, providing a secure hold with no clamp required.
Metric, BSPP, and UN/UNF (SAE Straight) male threads have a gasket or O-ring for a tight seal. UN/UNF (SAE Straight) threads are also known as O-ring boss threads.
For technical drawings and 3-D models, click on a part number.
(SAE Straight) Male
Threads with Gasket
Choose-a-Color Aluminum Low-Pressure Barbed Tube Fittings for Air and Water
- For Use With: Air, Lubricated Air, Water
- Temperature Range: -40° to 230° F
- Tubing: Use with hard (Durometer 75A-60D) EVA plastic, polyethylene plastic, polyurethane rubber or PVDF plastic
Color-code fittings for easy identification. Fittings are aluminum, which is lightweight with good corrosion resistance. The barb grips onto tubing, providing a secure hold with no clamp required.
Metric and UN/UNF (SAE Straight) male threads have a gasket for a tight seal. UN/UNF (SAE Straight) threads are also known as O-ring boss threads.
For technical drawings and 3-D models, click on a part number.
(SAE Straight) Male
Threads with Gasket
| For Tube ID | Thread Size | Material | Gasket Material | Max. Pressure | Choose a Color | Each | |
UN/UNF (SAE Straight) Threads | |||||||
|---|---|---|---|---|---|---|---|
| 1/16" | 1/4"-28 | Anodized Aluminum | Fiber | 125 psi @ 72° F | 00000000 | 00000 | |
| 1/8" | 1/4"-28 | Anodized Aluminum | Fiber | 125 psi @ 72° F | 00000000 | 0000 | |
| 0.17" | 1/4"-28 | Anodized Aluminum | Fiber | 125 psi @ 72° F | 00000000 | 0000 | |
| 1/4" | 1/4"-28 | Anodized Aluminum | Fiber | 125 psi @ 72° F | 00000000 | 0000 | |
Stainless Steel High-Pressure Barbed Tube Fittings for Air and Water
- Temperature Range: See table
- Tubing: Use with firm (Durometer 75A-95A) EVA plastic, polyethylene plastic, polypropylene plastic or PVC plastic
Fittings withstand pressures up to 250 psi. They are 303 stainless steel for very good corrosion resistance.
Metric, BSPP, and UN/UNF (SAE Straight) male threads have a gasket to protect against leaks. UN/UNF (SAE Straight) threads are also known as O-ring boss threads.
For technical drawings and 3-D models, click on a part number.
UN/UNF (SAE Straight)
Male Threads with Gasket
| For Tube ID | Thread Size | Material | Gasket Material | Max. Pressure | Temp. Range, °F | Number of Barbs | Each | |
UN/UNF (SAE Straight) Threads | ||||||||
|---|---|---|---|---|---|---|---|---|
| 1/16" | 1/4"-28 | 303 Stainless Steel | Viton® Fluoroelastomer Rubber | 250 psi @ 72° F | -40° to 500° F | Single | 00000000 | 00000 |
| 1/8" | 1/4"-28 | 303 Stainless Steel | Viton® Fluoroelastomer Rubber | 250 psi @ 72° F | -40° to 500° F | Single | 00000000 | 0000 |
| 0.17" | 1/4"-28 | 303 Stainless Steel | Viton® Fluoroelastomer Rubber | 250 psi @ 72° F | -40° to 500° F | Single | 00000000 | 0000 |
| 1/4" | 1/4"-28 | 303 Stainless Steel | Viton® Fluoroelastomer Rubber | 250 psi @ 72° F | -40° to 500° F | Single | 00000000 | 0000 |
| 4mm | 1/4"-28 | 303 Stainless Steel | Viton® Fluoroelastomer Rubber | 250 psi @ 72° F | -40° to 500° F | Single | 00000000 | 0000 |
Plastic Luer Lock Tube Couplings for Air and Water
- For Use With: Nylon Plastic: Air, Water
Polycarbonate Plastic: Air
Polypropylene Plastic: Water - Temperature Range: See table
- Tubing: Use with soft (Durometer 40A-65A) PVC plastic or silicone rubber
Made of plastic, these couplings are lighter in weight than metal luer lock couplings. They're a popular choice in labs because of their versatility—they fit any other luer lock plug, socket, syringe, or needle. Quick to attach and detach, they’re often used in lines that are frequently disconnected. They have a compact body for easy installation in tight spaces. Use them in low-pressure applications. These couplings are open-flow style, so there is no shut-off valve to stop the flow when they’re separated.
Nylon couplings have excellent impact and abrasion resistance. They’re for general purpose applications. Polypropylene couplings won’t absorb water and lose strength, even in high-humidity environments. They also stand up to chemicals, including solvents.
Plugs with a locking ring are more secure than those without a locking ring. Give the ring a half turn to lock these couplings in place. You can’t remove the locking ring.
Note: For a complete coupling, order a plug and a socket.
For technical drawings and 3-D models, click on a part number.
| Thread Size | Color | Clarity | Max. Pressure | Temp. Range, °F | Locking Ring Included | Pkg. Qty. | Pkg. | |
UN/UNF (SAE Straight) Threads | ||||||||
|---|---|---|---|---|---|---|---|---|
Nylon Plastic | ||||||||
| 1/4"-28 | White | Opaque | 40 psi @ 72° F | -20° to 200° F | With Locking Ring | 10 | 000000000 | 00000 |
Polypropylene Plastic | ||||||||
| 1/4"-28 | White | Semi-Clear | 40 psi @ 72° F | 35° to 150° F | With Locking Ring | 10 | 000000000 | 00000 |
| Thread Size | Color | Clarity | Max. Pressure | Temp. Range, °F | Pkg. Qty. | Pkg. | |
UN/UNF (SAE Straight) Threads | |||||||
|---|---|---|---|---|---|---|---|
Nylon Plastic | |||||||
| 1/4"-28 | White | Opaque | 40 psi @ 72° F | -20° to 200° F | 10 | 000000000 | 00000 |
Polycarbonate Plastic | |||||||
| 1/4"-28 | Clear | Clear | 40 psi @ 72° F | -20° to 200° F | 10 | 000000000 | 00000 |
Polypropylene Plastic | |||||||
| 1/4"-28 | White | Semi-Clear | 40 psi @ 72° F | 35° to 150° F | 10 | 000000000 | 0000 |
Brass Luer Lock Tube Couplings for Air
Quickly connect low-pressure air lines with these luer lock couplings. Made of brass, they are stronger and more durable than plastic tube couplings. These couplings have a nickel plating for extra protection against corrosive environments. Luer lock connections are universal, so you can connect any plug and socket to each other, regardless of the pipe or tube size. You can also connect them to syringes and needles. These couplings have a compact body, so they’re easy to fit in tight spaces. All are open-flow style, so there is no shut-off valve to stop the flow when the coupling is separated.
Note: For a complete coupling, order a plug and a socket.
For technical drawings and 3-D models, click on a part number.
- Temperature Range: -100° to 300° F
| Thread Size | Material | Max. Pressure | Each | |
UN/UNF (SAE Straight) Threads | ||||
|---|---|---|---|---|
| 1/4"-28 | Nickel-Plated Brass | 30 psi @ 72° F | 00000000 | 00000 |
- Temperature Range: -100° to 300° F
| Thread Size | Material | Max. Pressure | Each | |
UN/UNF (SAE Straight) Threads | ||||
|---|---|---|---|---|
| 1/4"-28 | Nickel-Plated Brass | 30 psi @ 72° F | 00000000 | 00000 |
- Temperature Range: -100° to 300° F
| Thread Size | Material | Max. Pressure | Each | |
UN/UNF (SAE Straight) Threads | ||||
|---|---|---|---|---|
| 1/4"-28 | Nickel-Plated Brass | 30 psi @ 72° F | 00000000 | 00000 |
- Temperature Range: -100° to 300° F
| Thread Size | Material | Max. Pressure | Each | |
UN/UNF (SAE Straight) Threads | ||||
|---|---|---|---|---|
| 1/4"-28 | Nickel-Plated Brass | 30 psi @ 72° F | 00000000 | 000000 |
Stainless Steel Luer Lock Tube Couplings for Air and Water
Use these luer lock couplings to quickly connect low-pressure air and water lines. Made of stainless steel, they’re more durable than plastic couplings. Luer lock connections are universal, so you can connect any plug and socket to each other, regardless of the pipe or tube size. You can also connect them to syringes and needles. These couplings have a compact body, so they’ll fit in tight spaces. All are open-flow style, so there is no shut-off valve to stop the flow when the coupling is separated.
303 stainless steel couplings have very good corrosion resistance.
316 stainless steel couplings have excellent corrosion resistance.
Note: For a complete coupling, order a plug and a socket.
For technical drawings and 3-D models, click on a part number.
- Temperature Range: 32° to 300° F
| Thread Size | Max. Pressure | Each | |
UN/UNF (SAE Straight) Threads | |||
|---|---|---|---|
316 Stainless Steel | |||
| 1/4"-28 | 45 psi @ 72° F | 0000000 | 000000 |
- Temperature Range: 32° to 300° F
| Thread Size | Max. Pressure | Each | |
UN/UNF (SAE Straight) Threads | |||
|---|---|---|---|
316 Stainless Steel | |||
| 1/4"-28 | 45 psi @ 72° F | 0000000 | 000000 |
Barbed Fittings for Plastic and Rubber Tubing—Chemicals
- For Use With: Alcohol, Coolant, Mild Bases
- Temperature Range: See table
- Tubing: Use with firm (Durometer 75A-80A) polyurethane rubber, PVC plastic, or Viton® fluoroelastomer rubber
Minimize leaks in your line—these fittings have a single barb that creates a smooth clamping surface for extra-tight connections. Fittings are polypropylene, which has very good chemical resistance as well as impact and abrasion resistance.
For technical drawings and 3-D models, click on a part number.
| For Tube ID | Thread Size | Material | Color | Clarity | Max. Pressure | Temp. Range, ° F | Pkg. Qty. | Pkg. | |
UN/UNF (SAE Straight) Threads | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| 1/4" | 1/4"-28 | Polypropylene Plastic | White | Semi-Clear | 120 psi @ 72° F | 32° to 250° | 10 | 00000000 | 00000 |
Luer Lock Tube Couplings for Plastic and Rubber Tubing—Chemicals
- For Use With: Acetic Acid, Bleach, Ethanol, Hydrochloric Acid, Nitric Acid, Phosphoric Acid, Sulfuric Acid
- Tubing: Use with soft (Durometer 40A-65A) PVC plastic or silicone rubber
A staple in labs, these couplings are highly versatile, fitting any luer lock plug, socket, syringe, or needle. They lock together with a push and turn, so they work well in lines that are frequently disconnected. Use them in low-pressure applications. They have a compact body for installation in tight spaces. Made of PVDF, they resist most acids, alcohols, and organic solvents. PVDF is also known as Kynar.
Note: For a complete coupling, order a plug and a socket.
For technical drawings and 3-D models, click on a part number.
| Thread Size | Material | Color | Clarity | Max. Pressure | Locking Ring Included | Pkg. Qty. | Pkg. | |
UN/UNF (SAE Straight) Threads | ||||||||
|---|---|---|---|---|---|---|---|---|
| 1/4"-28 | PVDF Plastic | White | Semi-Clear | Not Rated | With Locking Ring | 10 | 0000000 | 000000 |
Grease Fitting Adapters
When the size or thread type of a fitting doesn't match an existing opening, use these adapters to make the connection.
Zinc-plated steel adapters have mild corrosion resistance. 303 stainless steel adapters are more corrosion resistant than brass adapters and have good chemical resistance.
PTF-SAE and NPTF (Dryseal) threads are compatible with NPT threads. UNF threads are similar to threads on a machine screw or bolt. They require a sealant, such as an O-ring, to minimize leakage. SAE-LT threads are tapered but designed to be installed into a 1/4"-28 straight-thread UNF hole.
For technical drawings and 3-D models, click on a part number.
Connection | ||||
|---|---|---|---|---|
| Male | Female | Material | Each | |
Adapters | ||||
| UNF 1/4"-28 | NPT 1/8 | Steel | 0000000 | 00000 |
| SAE-LT 1/4"-28 | NPTF 1/8 | Zinc-Plated Steel | 0000000 | 0000 |
| SAE-LT 1/4"-28 | NPTF 1/8 | 303 Stainless Steel | 0000000 | 00000 |
| Metric M6 × 1 mm | UNF 1/4"-28 | Zinc-Plated Steel | 0000000 | 0000 |
| Metric M8 × 1 mm | UNF 1/4"-28 | Zinc-Plated Steel | 0000000 | 0000 |
| Metric M10 × 1 mm | UNF 1/4"-28 | Zinc-Plated Steel | 0000000 | 0000 |
Connection | |||||
|---|---|---|---|---|---|
| Male | Female | Material | Pkg. Qty. | Pkg. | |
Adapters | |||||
| SAE-LT 1/4"-28 | UNF 1/4"-28 | Zinc-Plated Steel | 5 | 0000000 | 00000 |
