Oxide treatment resists corrosion, helps prevent bit from rusting. Turbomax tip starts up to 10 times faster. Flatted shanks above 11/64 eliminates slippage in drill chuck. Reduced shank above 3/8 allows use of larger drill bits in a 3/8 chuck. Rubber overmolded case protects kit if dropped Tap and drill selection chart for convenience reference. Automatic indexing for easy bit access and identification. Removable cartridges: easy to carry bits from case to worksite. Set contains the following drill bit sizes: 1/16, 5/64, 3/32, 7/64, 1/8, 9/64, 5/32, 11/64, 3/16, 13/64, 7/32, 15/16, 1/4, 17/64, 9/32, 19/64, 5/16, 21/64, 11/32, 23/64, 3/8, 25/64, 13/32, 27/64, 7/16, 29/64, 15/32, 31/64, 1/2.