15 HSS Steel Carbide Drill Bit Watch Drilling Tool The is a new set of 15 high speed steel twist drill bits Great for drilling ferrous metals, tough casting sand forgings, working hardened stainless steel and other hard steels and tough high tensile strength nonferrous metals like titanium These bits measure approximately 0.3, 0.35, 0.4, 0.45, 0.5, 0.55, 0.6, 0.65, 0.7, 0.75, 0.8, 0.85, 0.9, 0.95 and 1 mm (0.011", 0.013", 0.015", 0.017", 0.019", 0.021", 0.023", 0.025", 0.027", 0.029", 0.031", 0.033", 0.035", 0.037" and 0.039")