Gas Disconnect Check Valve 1/4" FFL x 1/4" MFL

Sorry, but I have to agree with the last poster. I just purchased 6 of these, and every one of them leaked. I was able to stop the leak on 4 of them by tightening the heck out of them, but the other 2 required teflon tape. There is an internal O-ring, i think you need to build these with a bigger O-ring. I wasnt able to change the O-ring myself...

Had a lot of problems with back flow of beer into my gas lines and thought this would be a plug and play solution. I bought like 5 of these for all my gas lines and all of them leaked right from the start. I had to disassemble and teflon tape the heck out of them so they would not leak. I am still hesitant using these under constant gas as I don't want to lose a tank of co2 overnight from a slight leak. I expected for the price, these were plug and play out of the box. I am extremely disappointed in the quality for the price I paid per unit.