Abstract: A connector useful in releasably connecting well servicing equipment to wellheads. A male connector member houses resilient seals sealingly engageable in the female member on connection. The female connector member houses radially moveable dogs which may be locked in connecting engagement in a groove on the male connector by a lock sleeve longitudinally moveable over the dogs. The sleeve is longitudinally moveable in response to pressure and is biased toward dogs locked position and may be retained there by application of pressure through a first inlet in the sleeve. The female connector houses a pressure lock which prevents movement of the lock sleeve on application of pressure to a second lock sleeve inlet, if there is pressure in the connector bore.