Pneumatic Quick Disconnect Guide: What Fits What
Which of GW Kent's quick disconnects connect to each other, which match the fittings sold in hardware and auto parts stores, and which look similar but do not fit. These small fittings connect CO2 and air lines to tanks, keg washers, barrel transfer tubes, carbonation stones and air tools around the cellar.
The short answer: everything in the Pneumatic Socket and Plug family and the Pneumatic Quick Coupler family works together. The Quick Disconnect series in brass and stainless is a different style and does not.
1. Compatibility at a Glance
| Fitting family | Connects to | Matches these industry styles |
|---|---|---|
| Pneumatic sockets and plugs (stainless) | Each other, and pneumatic quick coupler plugs | Industrial Interchange, Milton M-style (I/M), built to MIL-C-4109F |
| Pneumatic quick couplers | Each other, and all pneumatic sockets | Milton V-style |
| Quick disconnects, brass or stainless | Only their own matching plug and socket | Hydraulic-style, self-closing; not interchangeable with the above |
2. Pneumatic Sockets and Plugs
- The sockets fit the common Industrial Interchange and Milton M-style plugs, both based on the MIL-C-4109F specification. In hardware and auto parts stores these are usually labeled "I/M" fittings, so a plug from your air compressor will usually fit a GW Kent socket.
- GW Kent's versions are all stainless steel, unlike most hardware-store versions.
- The sockets are true push-to-connect. You do not need to pull back the collar to connect a plug; just push it in. Pull the collar back to release.
- Sockets come with 1/4" male or female NPT threads. Plugs come with 1/4" male or female NPT threads or hose barbs.
Handy adapters
- Pneumatic plug to tri-clamp adapter: puts a gas connection on any tri-clamp port.
- Pneumatic plug to beer nut adapter: puts a gas connection on a beer-nut thread.
Both adapters also work with the pneumatic quick couplers below.
3. Pneumatic Quick Couplers
The quick coupler line is a newer series of sockets and plugs with hose barbs. The quick coupler plugs are physically larger and can carry more air, but they still fit all of the pneumatic sockets. They are compatible with Milton V-style quick disconnects.
4. Quick Disconnects (Not Compatible)
The brass and stainless steel Quick Disconnect series looks similar but is a different, hydraulic-style fitting. It does not connect to the pneumatic sockets, plugs or quick couplers.
- Works with liquid, air and vacuum.
- Sizes from 1/4" to 1", in brass or stainless steel.
- Sold only in pairs: a plug and a matching socket.
- Self-closing on both sides, so neither line drips when disconnected.
- Female NPT connections only.
5. Getting a Good Seal
Put a little food-grade lubricant on the male plug before you push it into a socket. It lubricates the socket's O-ring and improves the seal. This works on hardware-store fittings too.
Products
Pneumatic Socket, 1/4" Male NPT Pneumatic Socket, 1/4" Female NPT Pneumatic Plug, 1/4" Male NPT Pneumatic Plug, 1/4" Female NPT Pneumatic Plug, 5/16" Hose Barb Pneumatic Plug, 3/8" Hose Barb Pneumatic Plug to Tri-Clamp Adapter Pneumatic Plug to Beer Nut Adapter Pneumatic Quick Couplers Quick Disconnects, Stainless Quick Disconnects, Brass Food Grade Lubricant