- Oxide treatment resists corrosion, helps prevent bit from rusting
- Flatted shanks above 11/64-in eliminates slippage in drill chuck
- Reduced shank above 3/8-in allows the use of larger drill bits in a 3/8-in chuck
- Rubber overmolded case protects kit if dropped
- Tap and Drill selection chart for convenient reference
- Automatic indexing for easy bit access and identification
Premium high-speed steel withstands extended drilling in tough materials. Black and gold oxide finish provide maximum corrosion resistance. 135° split-point tip starts drilling immediately with less force and eliminates “walking” across the work surface. Metal index case for easy bit access and identification. Includes drill bit sizes 1/16-in to 1/2-in in 1/64-inch increments. IRWIN Tools Black and Gold High-Speed Steel Drill Bit, 29-Piece Set with Metal Index Case.