1. Made of chromium vanadium steel, integral heat treatment, strong impact force, high torque and good toughness.2. Electrophoresis surface treatment, not easy to rust and corrosion resistance.3. Has a 6-point opening, it can fit tightly to the hexagon of the fastener head so that the maximum torque can be applied without slipping.4. To prevent round-off under stress, it grips the flat sides of the fastener head rather than the corners.5. The through-hole in the drive end locks onto the tang of impact wrenches or drivers so it won't fall off or stick on fastener heads.6. Thicken-wall, electric wrench is available.7. For disassembly and tightening of hexagon head bolts and nuts, especially suitable for requiring large torque and narrow space. The product has no insulation properties and is not suitable for electrical environments.