Cobalt Red Helix Drill Bit Set for Drill Drivers (87-Piece). Cobalt alloy for up to 15 x life verses black oxide drill bits. QUADEDGE TIP designed to decrease heat build up and drill faster. Enhanced tapered web strengthens the bits core. VARIABLE HELIX design for rapid material extraction. 135° split point for precision start no walking. 3-flat secure-grip helps keep the bit fixed within the chuck. Designed for hard metals, PVC and wood. Quad edge tip decrease heat build up for faster drilling. Red helix for rapid material extraction. Enhanced tapered web increases flute durability, core strength. The Milwaukee RED HELIX Cobalt 87-Piece Drill Bit Set is engineered for extreme durability and longer life in hard metal applications. The Milwaukee Cobalt drill bits are designed with a VARIABLE HELIX that includes an aggressive 35° Helix Angle which ends at 15°. The drill bits have QUADEDGE TIP to decrease heat buildup and drill faster. The 135° split point tip delivers a precision start and prevents walking for fast, accurate holes in Hard Metal, PVC and wood. The tapered drill bits feature a new ENHANCED TAPERED WEB that strengthens the bit’s core to increase flute durability. The cobalt twist drill bits are ideal for tough applications, providing up to 15x life verses Black Oxide Drill Bits. This set includes 23 bits from 1/16 in. Drill Bit Type: Twist. Drill Bit Type(s) Included: Twist. Features: No Additional Features. Material Application: Duct/Sheet Metal, PVC, Wood. Number of Pieces: 87. Tools Product Type: Other.