6 Bottom Cleaning Drill Bits with 8mm Shank, Size: 8x18; 8*20; 8*22;8*25; 8*30; 8*32. Solid hardened steel body with anti-kickback design, build-up and heat resistant Teflon coating C3 micro-grain tungsten carbide burs , double edge cutting design, excellent concentricity Ideal woodworking tool for cutting all composition materials, plywoods, hardwoods and softwoods Contents of package: 6 bottom cleaning bits. Product Features: C3 Micro-Grain Tungsten Carbide Burrs. Strong hardened steel body with anti-kickback design. Teflon coating resists buildup and heat. Alloy blade with high quality welding , stable quality high efficiency. Cemented carbide built, great replacement for your old one. Specification: Material: cemented carbide Yellow Color Shank Diameter: 8mm Package Including: 6* Cleaning Bottom Router Bits Note: When trepanning, please wear good protective measures, in case of wood chip splash damage the eyes. Size for manual measurement, there may be have 0-5mm error, belongs to the normal phenomenon.