【Size】1/2-inch drive socket, M10 (10mm) spline bit, 4-inch (100mm) total length.【Durable】Quenched and heat treated S2 alloy steel bits, hardness arrived at 58-62 HRC, reduce wear-outs. High strength chrome vanadium steel sockets, increase turning power.【Torque Strength】Complete corrosion resistance and rust resistance, mirror-polished and chrome-plated sockets and phosphate bits finish.【Precision Bits】Automatically bit tips to ensure accurate size, chamfered ends insert smoothly into fastener head, reducing wear.【Tools】Use with ratchet to improve speed in tightening spline drive fasteners. And the product has no insulation properties and is not suitable for electrical environments.