Inline Flare Check Valve via William’s Brewing. About: “This inline check valve features ¼” barbs, and releases at 10 PSI. Useful in draft systems that operate at dispensing pressures of 10 PSI or higher. Not recommended for systems where you use a dispensing pressure of under 10 PSI. For gas lines only, not for liquid lines. Overall length 4¼”

It is possible for beer to flow backwards through CO2 lines. This check valve helps keep your beer out of those lines and helps to prevent dirty gas lines and QDs and a possible mess.

As of this posting, this is selling for just $4.99. Check product page for current price and availability.

IN LINE CHECK VALVE

Also at William’s:

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