Step 4-12mm drill bit from the professional tool brand Tvardy made of the highest quality HSS M2 high-speed steel with TiAlN coating. Drill stepped every 2 mm with a cylindrical handle and legible numbering. Intended for metals, thin-walled steel sheets, plastics. M2 steel is a high-quality tungsten-molybdenum tool steel, used for the production of the highest quality cutting tools. This steel has excellent cutting properties. High molybdenum content significantly improves hardenability, also increases impact strength and corrosion resistance. Tungsten, on the other hand, increases the abrasion resistance of steel, drills do not dull as quickly as those made of cheaper high-speed steels. The drill bits coated with a TiAlN layer are intended in particular for machining difficult-to-cut materials and wherever the drill will be subjected to high thermal loads due to the lack of coolant or limited coolant supply. This coating significantly improves the wear resistance of the drill bits and allows to increase the cutting speed. The drill is packed in a blister with a hole for hanging on a hook. Technical data: Type Step drill Stal HSS M2 Layer TiAlN  Chuck cylidrical Diameters [mm] 4, 6, 8, 10, 12, 14, 16, 18, 20 Stepped every 2 mm Total length [mm] 75 Working length [mm] 51