A detachable grip device has a body, two jaw-forming elements which are mobile in relation to each other between an open position and a closed position, a system for displacing the jaw-forming elements which are designed in such a way as to be able to alternate between a stable closing state and a stable opening state, via an intermediate state of unstable equilibrium, and a system for opening the jaw-forming elements. The opening system is adapted in such a way as to drive the displacement system initially in their closed state past the intermediate state of unstable equilibrium. The opening system comprises at least one button which is arranged on a longitudinal side of the body and is mounted in a sliding manner according to a direction of displacement having a component in the transverse direction.