From the product description, check product page for current description, price and availability:

Sleep a little easier knowing this gas in ball lock with built-in check valve has your back. The internal check valve allows gas to flow out, but won’t allow backflow of liquid into your gas system. Many manifolds and regulators already feature check valves, but this disconnect will keep liquid from ever entering your gas lines in the first place. Especially handy if you force carbonate your beer using the bev out dip tube!

Why we love it: Because we’ve had beer shoot back into our gas line and that sucks. At some point you will have a keg that is pressurized more than the pressure in your gas system. This could be caused by different carbonation levels, a keg sitting at room temperature, etc. So for example if the pressure in your keg is at 20 psi and your regulator is set at 12 psi, when you connect your gas in quick-disconnect liquid shoots from the keg into the gas line. Eliminate that possibility with this ingenious fitting.

Features:

• Internal Check Valve protects your system from liquid back flow
• Made in Germany and assembled in the USA by CMB.
• Extremely high quality for years of service.
• NSF Approved for Food Grade Service!

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