These U-shaped bits are made of high-quality S2 alloy steel, which is the material used has high hardness in the material. With a 1/4 inch hex shank, they are suitable for electric screwdrivers, hand screwdrivers, drills, pneumatic drilling, etc. For this set and make your life easier. Properties These U-shaped bits are made of high-quality S2 alloy steel, which is the material used has high hardness in the material. These bits are magnetic and can be firmly fixed on screwdrivers. The set included 5 U-shaped heads of different sizes, which can meet the requirement at an affordable price. Large scale used, suitable for electric screwdrivers, hand screwdrivers, drills, etc. It is convenient to use electronic device, ideal for electrician, mechanical repair. Specifications: Material: S2 Alloy Steel Head Shape: ‹ Handle: Hex Shank Handle Size: 6.35mm / 1/4" Length: 50mm / 2inch Specification: U4, U5, U6, U7, U8 Is it magnetic: Yes Quantity: 5PCS Dimensions Length(mm) U4 50mm / 2inch U5