Duotight fittings are easy to use to hook up your various draft system components! This part has a female threaded 1/4 in. flare fitting, which is perfect for gas and ball lock disconnects with a 1/4 in. male flare fitting. No flare washer required! The other end accepts 8 mm (5/16 in.) O.D. tubing and rigid plastic joiners. The high performance double o-ring design ensures superior sealing for Duotight connections. Simply insert tubing and firmly push to connect! Need to disconnect? Simply press in the collet fitting. It's just that easy!