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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.
Zinc-plated steel plugs are stronger and more durable than other metal plugs. They have fair corrosion resistance, so they should be used primarily in dry environments. 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. | Pipe Size | Max. Pressure | Each | |
Zinc-Plated Steel | ||||||
1/8 | 1/16" | 1/4" | 1/8 | 2,600 psi @ 72° F | 0000000 | 00000 |
1/4 | 1/8" | 3/8" | 1/4 | 5,500 psi @ 72° F | 0000000 | 0000 |
3/8 | 1/8" | 1/2" | 3/8 | 3,500 psi @ 72° F | 0000000 | 0000 |
1/2 | 1/8" | 5/8" | 1/2 | 2,700 psi @ 72° F | 0000000 | 00000 |
3/4 | 3/16" | 7/8" | 3/4 | 2,700 psi @ 72° F | 0000000 | 00000 |
1 | 3/16" | 1 3/16" | 1 | 2,000 psi @ 72° F | 0000000 | 00000 |
Brass | ||||||
1/8 | 1/16" | 1/4" | 1/8 | 2,500 psi @ 72° F | 0000000 | 0000 |
1/4 | 1/8" | 3/8" | 1/4 | 5,200 psi @ 72° F | 0000000 | 0000 |
3/8 | 1/8" | 1/2" | 3/8 | 2,700 psi @ 72° F | 0000000 | 0000 |
1/2 | 1/8" | 5/8" | 1/2 | 2,200 psi @ 72° F | 0000000 | 00000 |
3/4 | 3/16" | 7/8" | 3/4 | 1,700 psi @ 72° F | 0000000 | 00000 |
1 | 3/16" | 1 3/16" | 1 | 1,200 psi @ 72° F | 0000000 | 00000 |
1 1/4 | 1/8" | 1 7/16" | 1 1/4 | 1,700 psi @ 72° F | 0000000 | 000000 |
1 1/2 | 3/16" | 1 3/4" | 1 1/2 | 1,400 psi @ 72° F | 0000000 | 000000 |
303 Stainless Steel | ||||||
1/8 | 1/16" | 1/4" | 1/8 | 4,200 psi @ 72° F | 0000000 | 00000 |
1/4 | 1/8" | 3/8" | 1/4 | 7,500 psi @ 72° F | 0000000 | 00000 |
3/8 | 1/8" | 1/2" | 3/8 | 6,300 psi @ 72° F | 0000000 | 00000 |
1/2 | 1/8" | 5/8" | 1/2 | 3,600 psi @ 72° F | 0000000 | 00000 |
3/4 | 3/16" | 7/8" | 3/4 | 3,000 psi @ 72° F | 0000000 | 00000 |
1 | 3/16" | 1 3/16" | 1 | 2,000 psi @ 72° F | 0000000 | 00000 |
2 | 1/4" | 2 3/16" | 2 | 1,500 psi @ 72° F | 00000000 | 000000 |


- Maximum Pressure: See table
- Temperature Range: -40° to 250° F
- Compatible With: Hansen ST Couplings, Parker ST Couplings, Perfecting E Couplings


- 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. | Pipe Size | Max. Pressure | Each | |
Zinc-Plated Steel | ||||||
1/8 | 1/16" | 1/4" | 1/8 | 2,600 psi @ 72° F | 0000000 | 00000 |
1/4 | 1/8" | 3/8" | 1/4 | 5,500 psi @ 72° F | 0000000 | 0000 |
3/8 | 1/8" | 1/2" | 3/8 | 3,500 psi @ 72° F | 0000000 | 0000 |
1/2 | 1/8" | 5/8" | 1/2 | 2,700 psi @ 72° F | 0000000 | 00000 |
3/4 | 3/16" | 7/8" | 3/4 | 2,700 psi @ 72° F | 0000000 | 00000 |
1 | 3/16" | 1 3/16" | 1 | 2,000 psi @ 72° F | 0000000 | 00000 |
Brass | ||||||
1/8 | 1/16" | 1/4" | 1/8 | 2,500 psi @ 72° F | 0000000 | 0000 |
1/4 | 1/8" | 3/8" | 1/4 | 5,200 psi @ 72° F | 0000000 | 0000 |
3/8 | 1/8" | 1/2" | 3/8 | 2,700 psi @ 72° F | 0000000 | 0000 |
1/2 | 1/8" | 5/8" | 1/2 | 2,200 psi @ 72° F | 0000000 | 00000 |
3/4 | 3/16" | 7/8" | 3/4 | 1,700 psi @ 72° F | 0000000 | 00000 |
1 | 3/16" | 1 3/16" | 1 | 1,200 psi @ 72° F | 0000000 | 00000 |
1 1/4 | 1/8" | 1 7/16" | 1 1/4 | 1,700 psi @ 72° F | 0000000 | 000000 |
1 1/2 | 3/16" | 1 3/4" | 1 1/2 | 1,400 psi @ 72° F | 0000000 | 000000 |
303 Stainless Steel | ||||||
1/8 | 1/16" | 1/4" | 1/8 | 4,200 psi @ 72° F | 0000000 | 00000 |
1/4 | 1/8" | 3/8" | 1/4 | 7,500 psi @ 72° F | 0000000 | 00000 |
3/8 | 1/8" | 1/2" | 3/8 | 6,300 psi @ 72° F | 0000000 | 00000 |
1/2 | 1/8" | 5/8" | 1/2 | 3,600 psi @ 72° F | 0000000 | 00000 |
3/4 | 3/16" | 7/8" | 3/4 | 3,000 psi @ 72° F | 0000000 | 00000 |
1 | 3/16" | 1 3/16" | 1 | 2,000 psi @ 72° F | 0000000 | 00000 |


- 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. | Pipe Size | Max. Pressure | Each | |
303 Stainless Steel | ||||||
1/8 | 1/16" | 1/4" | 1/8 | 4,200 psi @ 72° F | 00000000 | 000000 |
1/4 | 1/8" | 3/8" | 1/4 | 7,500 psi @ 72° F | 00000000 | 00000 |
3/8 | 1/8" | 1/2" | 3/8 | 6,300 psi @ 72° F | 0000000 | 00000 |
1/2 | 1/8" | 5/8" | 1/2 | 3,600 psi @ 72° F | 00000000 | 00000 |
3/4 | 3/16" | 7/8" | 3/4 | 3,000 psi @ 72° F | 00000000 | 00000 |
1 | 3/16" | 1 3/16" | 1 | 2,000 psi @ 72° F | 00000000 | 000000 |


- Maximum Pressure: See table
- Temperature Range: -40° to 250° F
- Compatible With: Hansen ST Couplings, Parker ST Couplings, Perfecting E Couplings
Sockets | ||||||||
---|---|---|---|---|---|---|---|---|
For Plug Tip | Replacement Gaskets | |||||||
Coupling Size | Lg. | Dia. | Pipe Size | Max. Pressure | Each | Each | ||
Brass | ||||||||
1/8 | 1/16" | 1/4" | 1/8 | 2,500 psi @ 72° F | 0000000 | 000000 | 00000000 | 00000 |
1/4 | 1/8" | 3/8" | 1/4 | 5,200 psi @ 72° F | 0000000 | 00000 | 0000000 | 0000 |
3/8 | 1/8" | 1/2" | 3/8 | 2,700 psi @ 72° F | 0000000 | 00000 | 0000000 | 0000 |
1/2 | 1/8" | 5/8" | 1/2 | 2,200 psi @ 72° F | 0000000 | 00000 | 0000000 | 0000 |
3/4 | 3/16" | 7/8" | 3/4 | 1,700 psi @ 72° F | 0000000 | 00000 | 0000000 | 0000 |
1 | 3/16" | 1 3/16" | 1 | 1,200 psi @ 72° F | 0000000 | 00000 | 0000000 | 0000 |
303 Stainless Steel | ||||||||
1/8 | 1/16" | 1/4" | 1/8 | 4,200 psi @ 72° F | 0000000 | 00000 | 00000000 | 0000 |
1/4 | 1/8" | 3/8" | 1/4 | 7,500 psi @ 72° F | 0000000 | 00000 | 000000 | 00 |
3/8 | 1/8" | 1/2" | 3/8 | 6,300 psi @ 72° F | 0000000 | 00000 | 000000 | 00 |
1/2 | 1/8" | 5/8" | 1/2 | 3,600 psi @ 72° F | 0000000 | 00000 | 00000000 | 0000 |
3/4 | 3/16" | 7/8" | 3/4 | 3,000 psi @ 72° F | 0000000 | 000000 | 000000 | 00 |
1 | 3/16" | 1 3/16" | 1 | 1,700 psi @ 72° F | 0000000 | 000000 | 00000000 | 0000 |


- Maximum Pressure: See table
- Temperature Range: -40° to 250° F
- Compatible With: Hansen ST Couplings, Parker ST Couplings, Perfecting E Couplings


- Maximum Pressure: See table
- Temperature Range: -40° to 250° F
- Compatible With: Hansen ST Couplings, Parker ST Couplings, Perfecting E Couplings
Sockets | ||||||||
---|---|---|---|---|---|---|---|---|
For Plug Tip | Replacement Gaskets | |||||||
Coupling Size | Lg. | Dia. | Pipe Size | Max. Pressure | Each | Each | ||
Brass | ||||||||
1/8 | 1/16" | 1/4" | 1/8 | 2,500 psi @ 72° F | 0000000 | 000000 | 00000000 | 00000 |
1/4 | 1/8" | 3/8" | 1/4 | 5,200 psi @ 72° F | 0000000 | 00000 | 0000000 | 0000 |
3/8 | 1/8" | 1/2" | 3/8 | 2,700 psi @ 72° F | 0000000 | 00000 | 0000000 | 0000 |
1/2 | 1/8" | 5/8" | 1/2 | 2,200 psi @ 72° F | 0000000 | 00000 | 0000000 | 0000 |
3/4 | 3/16" | 7/8" | 3/4 | 1,700 psi @ 72° F | 0000000 | 00000 | 0000000 | 0000 |
1 | 3/16" | 1 3/16" | 1 | 1,200 psi @ 72° F | 0000000 | 00000 | 0000000 | 0000 |
1 1/4 | 1/8" | 1 7/16" | 1 1/4 | 1,700 psi @ 72° F | 0000000 | 000000 | 00000000 | 0000 |
1 1/2 | 3/16" | 1 3/4" | 1 1/2 | 1,400 psi @ 72° F | 0000000 | 000000 | 00000000 | 0000 |
303 Stainless Steel | ||||||||
1/8 | 1/16" | 1/4" | 1/8 | 4,200 psi @ 72° F | 0000000 | 00000 | 00000000 | 0000 |
1/4 | 1/8" | 3/8" | 1/4 | 7,500 psi @ 72° F | 0000000 | 00000 | 000000 | 00 |
3/8 | 1/8" | 1/2" | 3/8 | 6,300 psi @ 72° F | 0000000 | 00000 | 000000 | 00 |
1/2 | 1/8" | 5/8" | 1/2 | 3,600 psi @ 72° F | 0000000 | 00000 | 00000000 | 0000 |
3/4 | 3/16" | 7/8" | 3/4 | 3,000 psi @ 72° F | 0000000 | 000000 | 000000 | 00 |
1 | 3/16" | 1 3/16" | 1 | 2,000 psi @ 72° F | 0000000 | 00000 | 00000000 | 0000 |
1 1/4 | 1/8" | 1 7/16" | 1 1/4 | 2,200 psi @ 72° F | 00000000 | 000000 | 000000 | 00 |
2 | 1/4" | 2 3/16" | 2 | 1,500 psi @ 72° F | 00000000 | 00000000 | 000000 | 00 |


- Maximum Pressure: See table
- Temperature Range: -40° to 250° F
- Compatible With: Hansen ST Couplings, Parker ST Couplings, Perfecting E Couplings


- 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 | ||||||
1/8 | 1/16" | 1/4" | 1/4" | 4,200 psi @ 72° F | 00000000 | 000000 |
1/4 | 1/8" | 3/8" | 1/4" | 7,500 psi @ 72° F | 000000 | 00000 |
3/8 | 1/8" | 1/2" | 3/8" | 6,300 psi @ 72° F | 00000000 | 00000 |
1/2 | 1/8" | 5/8" | 1/2" | 3,600 psi @ 72° F | 00000000 | 00000 |
3/4 | 3/16" | 7/8" | 3/4" | 3,000 psi @ 72° F | 00000000 | 000000 |


- Maximum Pressure: See table
- Temperature Range: -40° to 250° F
- Compatible With: Hansen ST Couplings, Parker ST Couplings, Perfecting E Couplings
For Plug Tip | ||||||
---|---|---|---|---|---|---|
Coupling Size | Lg. | Dia. | For Hose ID | Max. Pressure | Each | |
303 Stainless Steel | ||||||
1/8 | 1/16" | 1/4" | 1/4" | 4,200 psi @ 72° F | 00000000 | 000000 |
3/8 | 1/8" | 1/2" | 3/8" | 6,300 psi @ 72° F | 00000000 | 000000 |
1/2 | 1/8" | 5/8" | 1/2" | 3,600 psi @ 72° F | 00000000 | 00000 |
3/4 | 3/16" | 7/8" | 3/4" | 3,000 psi @ 72° F | 00000000 | 000000 |
1 | 3/16" | 1 3/16" | 1" | 2,000 psi @ 72° F | 00000000 | 000000 |