Drills made of high speed steel standard DIN 338 with 5% cobalt additives. Drill solid unalloyed and alloyed steel. Coping with even color and stainless metals (aluminum), gray and ductile cast iron, as well as solid plastics. Cobalt drill bits are characterized by high wear resistance and long service life. Withstand high drilling modes, thanks to additives cobalt and features of the chemical composition of the alloy. Prolonged hard metal drilling recommend cooling oil, water and other solutions. ennoy wear resistance and long service life. Withstand high drilling modes, thanks to additives cobalt and features of the chemical composition of the alloy. Use these drills with a drill, shupurovertom or machine! Properties Drill highly alloyed, viscous and stainless steel, with a tensile strength of 1100 N / mm²; The exceptional resistance to degradation due to cobalt additives.