The Titanium Nitride (TiN) coating on this 50-piece high speed steel miniature drill bit set ensures significantly cooler cutting temperatures when used on wood, metal, plastic and more. Bits will last 4 times longer than standard bits. Includes ten each 1/16, 5/64, 3/32, 7/64 and 1/8 inch diameter drill bits packaged in a compartmented plastic organizer.