Duotight Flow Stopper Automatic Keg Filler for homebrew beer Corny Kegs Ball lock keg or Pin lock keg

Amazon.com Price: $16.92 (as of 11/08/2022 10:34 PST- Details)

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Use the Duotight Flow Stopper while filling kegs, during keg to keg transfers, or fermenter to keg transfers to automatically cut off the flow when the keg is full
Simply attach this device to the output gas post of your keg, then when the keg is full it will prevent further liquid exiting the gas post.