Stanley Proto J7210H 3/8-Inch Drive Impact Socket, 5/16-Inch, 6 Point Proto 6 Point Impact Sockets are ideal for use on stubborn or damaged fasteners and also on fasteners made from soft materials The TorquePlus design is a high performance drive configuration which allows for quick and easy socket engagement The TorquePlus configuration employs a radius-corner design, shifting contact area and stress away from the fastener corners The TorquePlus internal design minimizes fastener rounding, helps to extend fastener life Size stamped on tool for easy identification