Milwaukee® Step Drill Bit, Imperial, #12 Letter/Wire, 7/8 in Diameter Minimum Hole, 1-3/8 in Diameter Maximum Hole, 5 Steps, 4 Hole, 2 Flutes, 3/8 in Shank, 3-Flat/Reduced Shank, HSS Cutting Edge, HSS, Black Oxide, Applicable Materials: Metal and Plastic