High Quality Formwork Drill Bit:- Made of Chrome Vanadium Steel (CR-V), these bit holders are highly abrasion resistant and extremely hard for long life. Perfect Connection & Stable:- 3 different lengths: 60mm, 100mm, 150mm, perfectly match your working tools. This allows you to extend any type of screwdriver and use the screwdriver head conversion. Easy mounting and strong magnetism:- The magnetic screwdriver bit holder has a locking mechanism indispensable in interfaces, with built-in powerful magnet and automatic collector for quick attachment in the home and professional field. Universal & Convenient:- This bit holder set is a great tooling accessory for conversion, suitable for universal 1/4"" hex drill bits and drill bits. Application:- Suitable for DIY, profession, repairs and more. A must for renovation and hobby! Set of 3 bits of Magnetic Hexagonal Shank Screwdriver 60 mm 100 mm 150 mm for screws, nuts and all drill bits and hand screwdrivers Chromium vanadium is particularly