DEWALT 21 Piece Assorted Black and Gold Coated HSS Twist Drill Bit Set Plumbing Tool Chuck Type Keyed Housing Material Chuck Type Keyed Housing Material Aluminum Air Inlet Size 1 4 in Product Depth (in eyeglasses and tools 135 ° Split point tip design to help reduce walking High speed steel to be used in plastic and metal Tapered web design for extreme durability and resisting breakage Black and gold coating to help prevent rust and wear 3 Flats shank to reduce spin out in the chuck (on sizes larger than 3 16 in) Size markings on the drill bit shank for identifying sizes quickly Connectible accessory storage system to optimize storage space Patented bit bar design allows easy removal of bits and customizable placement Clear lid allows you to easily see contents at glance