Our 135-degree split point cobalt drill bits are particularly successful in cutting holes in harder grades of stainless steel and other material higher up on the Rockwell chart. Our patented M42+ alloy contains a higher cobalt percentage than the industry standard of 5-8 percent cobalt, rendering them super-friction-resistant and will cut more holes than most of our competitors, making the need to re-sharpen less frequent. Our popular 29 pc set includes sizes of 1/16” thru ½” by 64th increments.