Abstract: Clamping jaws assembly includes an elongate arm carrying pivotally at one end thereof a clamp body which itself supports pivotally two jaws on spaced parallel axes and a rod inter-connecting the jaws to limit their opening movement.A double-acting actuator connects one of the jaws and the arm and a telescopic, spring-loaded, device interconnects the clamp body and the arm.The actuator serves to pivot one of the jaws in relation to the other and beyond a predetermined part of its stroke also causes the whole of the clamp body to pivot about the arm so as to move outward of the plane on which the jaws take up workpieces.