Cornelius keg ball lock connector set. Set includes 1 - connector for gas in hookup and 1- connector for liquid out hookup. Both of these connectors have 1/4" barb fitting molded directly to the connector. No need for wrenches to connect barbed fitting. That means one less place for CO2 to leak out. Just push your 1/4'' i.d. hose onto the fitting and clamp with mini stainless steel hose clamp or plastic ratchet clamp.