Product description AUTO TOOLS drills are made of cobalt alloy tool steel R6M5K5 Cobalt 5%. The cobalt included in the steel composition allows maintaining hardness at high temperatures, which is especially important when drilling difficult-to-machine stainless steels. - They have high wear resistance. - The tip of the drills is cross-shaped sharpened at an angle of 135°, which allows drilling high hardness metals. - Hardness 64-67 HRC. - Packed in an envelope with a hole for storage convenience. The use of drills with increased wear resistance and hardness allows significantly saving the time spent on drilling and simplifies the work of the car mechanic several times.