General description M35 Cobalt Steel Drill Bit Set includes 50 pieces of high-speed steel (HSS-CO) drill bits, specifically designed for drilling on hardened steel, cast iron, and stainless steel. Made from M35 cobalt steel, these drill bits feature a hardened alloy with a hardness rating of up to 67, providing significantly deeper cutting and an extended lifespan, up to twelve times better than average drill bits. The set includes sizes ranging from 1mm to 3mm, with 10 pieces of each size. Technical specifications Material: M35 Cobalt Steel Hardness: Up to 67 HRC Sizes included: 1mm, 1.5mm, 2mm, 2.5mm, 3mm (10 pieces of each size) Color: Gold Measurement allowed error: +/- 1-3 cm Usage Ideal for drilling hard metals such as stainless steel and cast iron. Not recommended for hardened steel or high-carbon steel. Use coolant to extend drill bit life and prevent overheating and breakage. Adjust RPM if penetration is difficult. Be cautious when using smaller bits, as they are more prone