Hex drill bits come in 10 different sizes: 12mm, 10mm, 8mm, 6mm, 5mm, 4mm, 3mm, 2.5mm, 2mm, 1.5mm, to meet various needs. Length: 100mm. Handle Type: 6.35mm, 1/4 Inch. Mini handle screwdriver size: 120mm in length, compatible with 1/4 inch (6.35mm) hexagonal handle screwdriver head. This hexagonal drill bit is made of high-quality S2 steel, offering stable performance, high strength, good wear resistance, and hardness up to HRC60. The outer layer features a green wear-resistant rubber heat shrink tube, providing rust-proof and waterproof protection. The hexagonal screwdriver head includes an upgraded strong magnet, allowing easy pickup of screws and small parts, reducing the risk of dropping. It helps improve work efficiency and prevents damage to screws and screwdriver heads. Designed for secure fit, the hexagonal screwdriver head can be directly inserted into compatible tools and stays firmly in place. Suitable for use in vehicle, bicycle, furniture, engineering, machinery, and home appliance repairs. This hexagonal drill bit set is compatible with electric screwdrivers, manual screwdrivers, electric drills, air drills, and other similar tools. Note that it is not suitable for impact drills or electric wrenches.