WRENCH

Proto Tools is an American industrial hand tool company. Founded as Plomb, it is presently a division of Stanley Black & Decker. The company is credited with creating the first combination wrench in 1933. Proto Spline Tools are designed to service high tensile strength fasteners used widely on military and commercial aircraft and in heavy machinery applications where vibration is prevalent. They are also used in automotive and industrial areas where high performance torque needs to be achieved Spline fasteners help tighten high strength bolts to high torque loads They help lower the force required to turn standard fasteners by allowing the torque load to be moved away from the corners, helping prevent fastener rounding. They also turn fasteners with damaged corners