Stanley J49038S2 Proto 3/8-inch Roll Pin Punch One piece design for strength and durability. Reverse taper to help prevent binding. Made from S2 steel and specially heat-treated for greater strength and durability. Modified parabolic striking end to help reduce mushrooming and chipping. Black oxide finish to help prevent rust corrosion; extending tool life and performance. A polished identification panel on one of the flats is marked with the tool number and size in a black inlay.