Abstract: A tubular metal coupling body defines a chamber which receives an axially movable tubular actuating member defining a bore for receiving an end portion of a metal tube. A counter-bore within the actuating member receives a resilient sealing ring and a compression collar, and a tube gripping spring collet is supported by a retainer confined within a cap threaded onto one end portion of the coupling body. A tubular actuating sleeve surrounds the body and is retained for limited axial movement, and a fitting is threaded into the opposite end portion of the body. A set of circumferentially spaced levers are supported within corresponding slots in the body for pivotal movement in radial directions and move the actuating member axially between released and gripping positions in response to axial movement of a cam surface within the sleeve.