A power gripper for a machine or robotic tool having a housing provided with a cylinder and piston for actuating a pair of finger carriers slidably mounted on the housing to reciprocate between open and closed positions wherein the range of opening is enhanced for a gripper of a given size. This is attained by the piston rod having a rack portion meshing with an idler pinion that is in meshing relationship with a rack formed on one of the finger carriers whereby the latter is synchronized relative to the movement of the piston. The other finger carrier is pinned to the piston to move therewith. In one form of the invention, a fluid pressure acting on the opposed ends of the piston effects the drive of the piston in either direction. In another form of the invention, a fluid pressure is imparted on one end of the piston only and which piston is spring biased to effect the drive of the piston in the opposite direction.