Milwaukee 48-89-2332 29 pc. Cobalt RED HELIX Drill Bit Set. 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° helix angle which ends at 15°, the cobalt bits with RED HELIX provide Rapid Chip Removal limiting heat buildup to Stay Sharper Longer.