YAJU [High Quality]: These burrs are made of tungsten carbide steel for high hardness and high abrasion resistance [Widely Used]: Could cut cast iron, cast steel, carbon steel, alloy steel, stainless steel, copper, aluminum, marble, jade, bone, etc. This rotary burrs can be widely used for carving, shaping and for the removal of sharp edges or corners, burrs and excess material [High Productivity]: The processing efficiency of the tungsten carbide steel rotary file is more than ten times higher than that of manual files, and nearly ten times higher than that of small grinding wheels with handles [Unique Design]: The shank diameter of this rotary file is 3mm, would be suitable to fit many electric powered or pneumatic powered tools. With double cut and single cut for you to choose [Package]: There are total 10 pieces burrs in various shapes that you can use for multiple purposes Specifications: color: as show Material: Tungsten carbide steel Type: Double Cut Shank Diameter: 3mm Cutting Head Diameter: 6mm Speed: 1000~3700R/min Processing Hardness: 85HRA Package Includes: 10 x Rotary Burrs