Irwin Industrial Tools 10234CB #4 Unibit 3/16- Inch - 7/8-Inch, 12-Steps Cobalt Step Drill Bit (1/16- Inch Steps)
Irwin Unibit Cobalt is made of high speed steel, this step drill bit will last longer in the toughest of materials. Irwin Industrial Tools 10234CB 4 12 Hole Sizes (3/16-Inch-7/8-Inch), 1/16-Inch Increments