Bosch, Craftsman, Delta, Dremel, Dewalt, Hilti, Klein, Kobalt, Lenox, Makita, Maximum, Milwaukee, Porter Cable, Ridgid, Rockwell, Ryobi, Skil, Stanley, Worx Titanium-Coated HSS Step Drill Bit. $20 10-45mm, 8 steps, 7.5mm each step.
