Compatibility: all shank size is 3 mm, allowing them to be compatible with most die grinders and rotary tools as you finish, grind, and shape your work effectively; Just install it like any other typical drill bit and bring you much convenience Engraving drill bit set: you will receive 10 pieces/ 2 sets wood carving and engraving drill accessories, which are enough for you to use, and help you to make kinds of crafts without breaking the wood, get a nice and smooth finished craft effect Material: made of high speed steel material, durable and sturdy for you to use, and not easy to break, offer nice cutting power and durable; These burrs are intended for faster wood removal, you can easily work with woods more faster while leaving a smoother finish Size information: our carving drill bit measures approx. 3 x 3 mm, 3 x 4 mm, 3 x 5 mm, 3 x 6 mm, 3 x 7 mm, 3 x 8 mm in shank and bit diameter, the different size can satisfy your various using needs Application: mainly applied for carving and engraving drill bit, also suitable for beginners or skilled people, ideal for handmade DIY carving making, you can also share them with your friends or family members