Features: Double Cut cylinder with variants shape. Made of heat-treated Tungsten carbide YG8 that lasts 10 times working life than HSS, suitable for machining various kinds of metal material including ≤HRC65 hardened steel. Widely used for metalwork, welding, wood carving, model engineering, jewelry making, deburring, grinding, cylinder head porting and sculpting. Suitable for all skill level | this is an essential kit for woodworkers & enthusiasts who clean up welds or works with metal frequently, easy to grasp and use, safe and reliable. Generally can be used with handheld electric or pneumatic tool drive (can also be used in the machine tool, and the speed of the electric/pneumatic tools usually about 6000-50000 RPM) Specification: color:silver Material:High speed steel Package include: 1 set x 20 piece set of high speed steel woodworking rotary file milling cutter Note: Please allow 1-3 cm differs due to manual measurement. Due to the different display and different light, the picture may not show the actual color of the item. Thanks for your understanding.