Feature 1These burrs are made of tungsten carbide steel for high hardness and high abrasion resistance 2There are total 10 pieces burrs in various shapes that you can use for multiple purposes 33mm round shank would fit many electric powered or pneumatic powered tools 4Could cut cast iron, cast steel, carbon steel, alloy steel, stainless steel, copper, aluminum, marble, jade, bone, etc 5Widely used for carving, shaping and for the removal of sharp edges or corners, burrs and excess material Description: This is a set of 10 pieces rotary burs in various shapes for multiple purposes, and it can be used tocut cast iron, cast steel, carbon steel, alloy steel, stainless steel, copper, aluminum, marble, jade, bone, etc. Features: These burrs are made of tungsten carbide steel for high hardness and high abrasion resistance. There are total 10 pieces burrs in various shapes that you can use for multiple purposes. 3mm round shank would fit many electric powered or pneumatic powered tools. Could cut cast iron, cast steel, carbon steel, alloy steel, stainless steel, copper, aluminum, marble, jade, bone, etc. Widely used for carving, shaping and for the removal of sharp edges or corners, burrs and excess material. Specifications: Material: Tungsten carbide steel Type: Double Cut, Single Cut(optional) Shank Diameter: 3mm Cutting Head Diameter: 6mm Speed: 1000~3700R/min Processing Hardness: 85HRA Note: Rotary file in pneumatic or electric tools, the speed is generally 1000~3700R/min, must clamp the tool firmly. Package Includes: 10 x Rotary Burrs