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 burrs , 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 Stem diameter: 8 mm Package including: 6 *cleaning lower router bits Note: When trepanning, please wear good protective measures, in case of splashing wood chips will damage your eyes. Size for manual measurement, there may be 0-5mm error, belongs to the normal phenomenon.