The ultimate Drill Bit Set! 115 sizes in High Speed Steel with Titanium Nitride coating. Sizes: #1 - #60 with equivalent dimensional sizing clearly marked in thousandths of an inch, 29 fractional bits from 1/16 inch to 1/2 inch by 1/64 inch increments, and 26 letter bits, A - Z. All bits are ground to 118 degree pointed angles for general purpose use on wood, metal, and plastic as well as most other materials. Comes in a sturdy metal box with easy-access racks.