Milwaukee cobalt red helix drill bits are engineered for extreme durability and long life in hard metal applications. Designed with a variable helix that includes an aggressive 35 deg helix angle which ends at 15 deg, the cobalt bits with red helix provide rapid chip removal limiting heat build-up to stay sharper longer. The 135 deg split point tip delivers a precision start and prevents walking for fast, accurate holes. Ideal for tough applications and provide Up to 15X life vs. black oxide drill bits but can be used in all twist drilling applications.