Product Description IRWIN Tools 3018006B Metal Drill Bit Set offers a versatile selection of sizes featuring the Turbomax tip, which eliminates "walking," gets faster starts, and stays sharp longer. The drill bits are made from premium high speed steel with black and gold finish for added corrosion resistance. Ideal for drilling mild steel, sheet metal, alloy steel, aluminum, stainless steel, brass, wood and plastics. The set comes in a metal index case with protective rubber overmolds to prevent damage if dropped, and is designed with removable cartridges for easy bit access and portability. A convenient tap and drill selection reference chart is also included. Contains sizes 1/16" through 1/2" in increments of 1/64". Bit sizes larger than 3/8" have a reduced shank, which allows them to be used in a standard 3/8" chuck. From the Manufacturer Irwin Industrial Tools 3018006B 29-Piece Drill Bit Industrial Set Case, TurboMax. Irwin offers a complete line of Metal Twist Drill Bits, including Black Oxide, Turbo Point, Titanium Nitride and Cobalt Drill Bits.