SpecificationsLength: 60mm (2.36inch) Shank shape: hexagonal shank Shank Diameter: 6.35mm (1 or 4 inch) Premium QualityMagnetic bit holder made of high quality chrome vanadium alloy steel, good abrasion resistance, durability and high hardness, durable Convenient magnetismMagnetic extension rod, interface with locking mechanism, strong magnet inside, fast fixing, can effectively improve work efficiency CompatibilityUniversal 1 or 4" hex shank of the magnetic bit holder fits most drills and power screwdrivers, allowing quick release and replacement Wide Application Suitable for air and electric screwdrivers, air drills and hand screwdrivers Fits most screwdriver bits Used in garages, warehouses, offices, homes, automobiles, etc 3pcs 60mm Magnetic 6.35mm Hex Shank Screwdriver Extension Bars Made of chrome vanadium steel (CR-V), so these bit holders have very good abrasion resistance and hardness extreme for a long service life. Interface with locking mechanism, strong magnet inside, quick fixing, automatic batch head jump. It can effectively improve work efficiency. Quick fixing, improve work efficiency. It can be used to lengthen all kinds of screwdriver bits. Hexagonal shank 1 or 4" universal: suitable for transfer drill, screwdriver, batch head and others, to lengthen all kinds of screwdriver bits and convert the screwdriver head. Suitable for DIY , profession, repairs and more.A must have for DIYers and hobby screwdrivers! SpecificationsMaterial: Chrome Vanadium Steel Hex Shank Diameter: 1 or 4 inch (6.35mm) Length: 2 inch (60mm) Package includes 3pcs 60mc Screwdriver Magnetic Extension Bars