It is a Repair Tool/Hand Tools/Hand Twisting Drill/DIY Tool. Chuck Diameter: 0.4”. Material: Aliminium Alloy Hand Drill & High Speed Steel Twist Bits. Application: Mainly used for Wood, Resin, Jewelry, Walnut, Amber, Beeswax, Olive Nut, Vajra Bodhi, Beads, Ivory Nut, PVC, Acrylic and Plastic etc.