Century Drill & Tool ratchet

Century 21-piece cobalt drill set

This 21-piece set from Century Drill & Tool uses M35 steel with 5% cobalt to cut extremely hard metals including stainless steel. The 135° quick-cut points are self-centering and penetrate faster with less pressure, preventing the bit from walking at the start. Designed for high heat resistance, the bits require power units running at 1500 RPM or more for maximum efficiency. Sizes range from 1/16" to 3/8" by 64ths.

Suited for metalworkers drilling stainless

Workers who need self-centering points and cobalt heat resistance for tough alloys will benefit from this set. It is not for users limited to drills below 1500 RPM, as the bits require higher speed for peak performance. Buyers who need sizes larger than 3/8" or smaller than 1/16" must look elsewhere. The transparent case color may not suit those wanting a metal index.

Covers 1/16" to 3/8" in 64th increments

The 21 bits handle common fractional sizes from 1/16" through 3/8" for general metal drilling tasks. Cobalt construction provides headroom for sustained cutting in stainless steel without rapid dulling. The set runs out above 3/8" diameter, so larger holes require separate bits. RPM below 1500 reduces cutting efficiency and bit life in hard materials.