D50463611 - HSS Step Drill For use in sheet metal, aluminium, plastic & fibre glass, ideal for sheet metal without pre-drilling. During drilling, the next step deburrs the previously drilled hole. Fixed Drilling Steps: Spiral Flute for reduced vibration and greater control through steps Made from HSS: Constructed from M2 high speed steel offering the best combination of strength, heat & wear resistance Flat Shank: Three flats suits 3-jaw chuck Shank - Flat Steps 11 Range 6, 9, 12, 15, 18, 21, 24, 27, 30, 33, 36mm