Abstract: A machine vise is provided comprising a body, a fixed jaw at one end which is adaptable for accomodating irregularly shaped workpieces, a movable jaw mounted on the body and slidable toward and away from the fixed jaw, a cam for urging the movable jaw into gripping relation with a workpiece disposed between the jaws and a pair of wedge elements for locking the cam in a fixed longitudinal position with respect to the body.