Description 100% brand new and high quality Material: Drill Head: HSS 4241 Intermediate chamfering drill body: Steel 45 Great drill accessory for any work shop backed by manufacturer's lifetime warranty. Heat treated & tempered high-carbon steel with titanium coating for superior cutting power. Use on steel, aluminum & other metals, plastic or wood. Enlarge or countersink holes, deburr edges, 15-degree chamfer. Three Pointed Woodworking Drill Bit Diameter: 3mm, 4mm, 5mm, 6mm, 7mm, 8mm, 10mm/0.12", 0.16", 0.20", 0.24", 0.28", 0.31", 0.39" (Approx.) Chamfer Diameter of 3mm, 4mm, 5mm, 6mm, 7mm Drill Bit: 15.8mm/0.62" (Approx.) Chamfer Diameter of 8mm,10mm Drill Bit: 17.8mm/0.71" (Approx.) Packaging: 4 pcs Set: 3mm, 4mm, 5mm, 6mm 7 pcs Set: 3mm, 4mm, 5mm, 6mm, 7mm, 8mm, 10mm