Product Description PROTO J72106 3/8" Drive 15 Piece Impact Socket Set - 6 Point From the Manufacturer All Proto impact sockets incorporate the TorquePlus wrenching system. The TorquePlus design is a high performance drive configurationwhich allows for quick and easy socket engagement to the fastener flats, not the corners. The configuration employs a radius-corner design, shifting contact area and stresses over a large area of the socket, minimizing slippage. The internal design of the TorquePlus minimizes fastener rounding, helps to extend fastener life, and allows the user to more easily turn worn, rounded, or rusted fasteners. Proto impact sockets are made from special alloy steel, and are heat treated for the correct balance of strength and hardness, while the one-piece construction ensures their concentricity. Socket wall thickness is optimized to provide maximum strength and ample access to restricted fasteners. Sockets are manufactured to the most up to date industrial specifications, assuring concentric openings, large clearance holes, and tight nut end tolerance.