The CRL Unibit Step Drill Set uses a unique, single flute design to drill perfectly round holes in thin materials. Cutting steps of progressively larger diameters make it possible to drill up to 13 different hole sizes with a single bit. Also, the hole is automatically deburred by the cutting edge of the next size up.

Hole starting is easy because it won't skid across the surface, even without center punching. Designed for use with steel, copper, brass, aluminum and other thin metals, it can also be used on plastics without chipping or clogging.

This set contains three drills which provide a range of holes from 1/8" to 3/4" (3.2 to 19 mm) in two bits, plus 3/16" to 1/2" (4.8 to 12.7 mm) holes in materials up to 3/8" (10 mm) thick on the other bit.