Forged with chromium molybdenum steel material, surface heat treatment, high strength and durability.To prevent rust and corrosion, the black phosphate finish absorbs and retains oil, repelling moisture.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.It has a radius corner design, causing the socket to grasp the sturdy wall of the fastener instead of the corners, thereby reducing the wear of the fastener.Widely used in DIY hand-making, household maintenance, and most general repairs.Specification:Driver Size: 1/4 InchBit Size: H3 H4 H5 H6 H7 H8 H10Total Length: 35mm / 1.38 InchMaterial: Chrome Molybdenum Steel (CR-MO)Finish: PhosphatingColor: BlackPackage Content:1 Set (7 Pcs) x Hex Bit Socket.