Drill Bit Set, 29 Piece, Titanium, 1/16" to 1/2", by 64ths, with 3/8" Reduced Shanks, in Metal Index IRWIN offers a complete line of Metal Twist Drill Bits, including Black Oxide, Turbo Point, Titanium Nitride, and Cobalt Drill Bits.. Lasts up to 6X longer than standard high-speed steel bits by reducing surface friction. Titanium Nitride Coating extends cutting edge life up to 6x. 135 split point tip starts on contact, cuts with less force. Reduced shank above 3/8" allows the use of larger drill bits in a 3/8" chuck. Rubber overmolded case protects kit if dropped. Tap & Drill selection chart for convenient reference.. Automatic indexing for easy bit access and identification. Removable cartridges: easy to carry bits from case to worksite.