Abstract: In a releasable plug-in socket coupling for one or more pipes or pipe elements sealingly insertable into a socket member, an annular groove-like chamber is provided for receiving a retaining element in the front area of the socket member.The retaining element, comprising individual, segmental portions, is held in the chamber by an elastic retaining ring. Each portion is tiltably supported with a correspondingly constructed top portion in the outer circumferential surface of the chamber and has on the side facing the pipe end surface a base portion provided with a first cutting edge and a second cutting edge spaced therefrom.An axially removable release ring is in operative connection with the retaining element so that when the release ring is axially displaced, the ring pivots the tiltable portions into the release position.