These M35 high speed steel drill bits are manufactured with 5% cobalt for long-lasting performance, abrasion resistance and heat protection. Fully ground with a 135 split point for precise centring to prevent drill wander. For optimal results and a longer lifetime, Draper cobalt drill bits work best in conjunction with a cooling agent. Suitable for use with alloy steel, titanium alloys, stainless steel, hardened steel, cast iron and carbon steel. Compatible with a standard 10/13mm chuck.