60mm 1/4 Inch Hex Shank Quick Release Screw Magnetic Drill Screwdriver Bit Holder Material:CR-V; Dimension: 1/4" hex shank (6.35mm), Length: 60mm Package included:1 pc Quick Release Screw Suitable for drill, screwdriver, batch head and other to transfer Interface has a locking mechanism, built-have magnetic, automatically pop up batch head Extend all kinds of screwdriver bits, screwdriver head conversion uses