Descriptions: These screwdriver bits are adopted of S2 quality steel, which is anti-impact and tough, great wear resistant.Magnetic head, so they can fixed on the screw firmly. Features: These screwdriver bits are magnetic head, so they can fixed on the screw firmly. Adopted of high quality S2 quality steel, which is anti-impact and tough, great wear resistant. With 1/4" hex shank, they are widely used on electric screwdrivers, hand screwdrivers, electric drills, etc. There are different type screwdriver bit heads, such as: Slotted head, cross head, security star head. So is convenient to you, can meet your varied requirements. Suitable for professional maintenance personnel, computer maintenance, camera maintenance, eyeglasses maintenance, instrument maintenance. Specifications: Material: S2 quality steel Hardness: HRC60 Hex shank size: 6.35 mm/(1/4") The total length: 100mm/3.94inch Security Star: T8, T10, T15, T20 Slotted: Dia. 6mm, Dia. 5mm, Dia. 4mm Cross(PH2): PH2 Dia. 6mm, PH2 Dia. 5, PH2 Dia. 4.5 Head type: Slotted head, cross head, security star Weight: 170g Quantity: 10 PCS Package Included: 10 x Screwdriver Bits