This M35 cobalt drill bit set is purpose-built for the toughest drilling challenge in metalworking: stainless steel. The addition of 5% cobalt to the high speed steel matrix substantially improves red hardness, allowing the cutting edges to retain their strength at elevated temperatures where ordinary HSS bits soften and fail quickly. This makes the set an essential choice for fabricators, pipe fitters, shipyards and maintenance teams that regularly drill into 304, 316 and
