Abstract: A quick connect coupling assembly includes a socket defined by a stepped bore in a body member, a tubular retainer nut threadingly received in the socket and a plug member carrying an O-ring seal that extends through the retainer nut and into the socket an axial extent whereby the O-ring seal is positioned to effect a seal relative to the plug member and an internal wall of the socket. The retainer nut having a shank portion defining circumferentially spaced apart flexible retainer fingers adapted to abut against an inclined radial shoulder of the plug member to effect its axial operative position within the socket.