Triumph® Step Drill, Series: TSD, Imperial, 1/4 in Diameter Minimum Hole, 3/8 in Diameter Maximum Hole, 10 Steps, 10 Hole, 10 Flutes, 1/4 in, 3/8 in, 1/2 in, 5/8 in, 3/4 in, 7/8 in, 1 in, 1-1/8 in, 1-1/4 in, 1-3/8 in, 1/4 in Shank, 3-Flat Shank, 135 deg Point, Split/Self-Centering Point, HSS Cutting Edge, HSS, Bright, Applicable Materials: Alloy Steel