Abstract: The disclosure concerns a hollow socket and hollow plug therefor and a specific snap clip for locking the plug in the socket by normally bridging radially aligned cooperating grooves in said plug and socket. The plug and socket may include cooperating surfaces between which a gasket or O-ring may be seated for sealing the coupling. The clip primarily comprises a pair of cooperating semicircular diametrically oppositely movable semiannuli or ring sections connected at one of their adjacent parallel ends by an integral spring loop extending substantially axially from the plane of the semiannuli or ring sections. This loop is provided with a pair of parallel legs joined at one end to the adjacent parallel ends of said semiannuli and at their other ends to a more than semi-circular ring. This loop normally urges said semiannuli outwardly into the groove in the socket.