Abstract: A coupling for attachment to the end of a pipe comprising: a tubular housing open at opposite ends, one end being adapted to fit over the outside of a pipe end to which the coupling is to be attached and the other end being adapted to have a valve connected thereto; a clamping device within said housing for clamping the housing to the outside of the pipe end, the device including a plurality of circumferentially-arranged tapered radially adjustable segments and a mechanism for moving the segments radially inward into edge-to-edge abutment with each other so as to form a frusto cone having its larger end facing the pipe end, each segment at its wider end being in sliding sealing engagement with the inner surface of the housing and each segment at its smaller end having at least one gripping surface which faces radially inward so as to form a circumferentially continuous gripping surface when the segments are in their radially inward position, there being a space between the outer surfaces of the segments and t