Set features industrial-quality roll-forged M2 high speed steel bits that are titanium coated to 102 Rockwell hardness. Set includes 60 wire gauge bits (numbered 1 through 60), 26 lettered bits (A through Z), and 29 fractional bits (1/16" through 1/2" in 1/64" increments). Larger bits (W through Z) are made for a 1/2" drill chuck only (not included) and may not fit in a standard 3/8" hand-drill chuck. Bits come packaged in a 3-section, indexed, enameled steel case for ease of storage.