CNBTR 0.5-3.2mm Brass Collet Drill Chuck Fits Dremel Rotary Tools Electric Grinding Drill Collect Chuck Holder Pack of 10 (4.3mm Shank Dia.) High quality brass collects to fit some rotary tools, pin vises. High quality brass collects to fit some rotary tools, pin vises. Made of pure copper material, made by special heat treatment, it has higher hardness and durability. Suitable for installation drill, electric grinding ,hanging mill ,hose above. Compatible with most rotary tools used in hardware, hobby, home etc.