[High Precision and High Strength] - Made of strong and durable tungsten alloys, the high quality drill bit ensures professional and ultra-precise machining on wood. [Long Time Use] - Clean cutting, smooth rotation, fast operation, high hardness, good wear resistance, greatly improve service life. [Solid Anti-Kickback Design] - Hardened steel body with balanced anti-kickback design with high quality guide and bearings. [Shank Diameter: 8mm] - Blade Diameter: 12mm; Blade length: 13mm. [Usage] - For crafts or woodworking; MDF, solid wood, particle board, wooden door frames, wooden window frames, cabinets and boxes. Features: Stable quality and high efficiency blade with upper and lower bearings. Carbide Tipped - Micro-grain grade provides increased strength and maximum strength. Heat-resistant coating baking to prevent the build-up of wood chips, resin and asphalt. Specification: Material: Carbide Blade Length: 13mm, 20mm, 25mm Color: Black, Yellow, Blue Package Included: 3 Size X Grooving Cutter