Shank Diameter: Ф4mm-Ф12mm Length: 50mm-100mm Blade Material: Tungsten Steel Flute: 4 Flutes Coating: Tian Coat Mill: Face/Side Milling Feed Speed:8M-12M Per Minute Principal Axis RPM:18000-24000 RPM Hardness of Razor Blade:93-94.5 Machine:Carving Machine,Electric Wood Milling Machine,Deflasher(1/4' Shank),Crane Tower,CNC etc. Drills Materials: Wood, Plywoods, Pinewood, Hardwoods,MDF, Solid Surface Materials ,and Softwoods. Features: 1 In design with curve, the head is good at removing the debris and working efficiently. 2 The tip is specially designed to cut through hole cleanly, great for boring concealed hinges and door locks. 3 Guided by the Circular Rim, Bores Any Arc of a Circle, in any direction, great for drilling flat bottom holes, pocket holes, or overlapping holes. 4 Suitable for drill press, pistol drill, bench drill, vertical drilling machine, stand motor-driven drilling machine and mobile ribbon type magnetism drilling machine etc.