* Made of chrome-moly steel construction for strength and durability.* To prevent rust and corrosion, the black phosphate finish absorbs and retains oil, repelling moisture.* Has 6-point opening that snugly fits the hex shape of fastener heads, allowing it to apply maximum torque without slipping.* To prevent round-off under stress, it grips the flat sides of fastener heads instead of the corners.* The through-hole at the drive end locks on the tang of drivers or impact wrenches, so it won't fall off or stick on the fastener head.* Widely used in DIY hand-making, household maintenance, and most general repairs.
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