CO2 Quick Coupler - Female (5/16" Barb)
CO2 quick disconnects make swapping out gas line a breeze. With a check valve on the female side of the connection gas flow stops when they're disconnected. So you can be sure not to accidentally drain your co2 tank when moving tanks or hoses.
This is the female coupler and has a 5/16" barb. Pair it with the male CO2 quick coupler.