Triumph® Step Drill, Series: TSDHEX, Imperial, 1/4 in Diameter Minimum Hole, 3/4 in Diameter Maximum Hole, 9 Steps, 9 Hole, 9 Flutes, 1/4 in, 5/16 in, 3/8 in, 7/16 in, 1/2 in, 9/16 in, 5/8 in, 11/16 in, 3/4 in, Hex Shank, 135 deg Point, Split/Self-Centering Point, HSS Cutting Edge, HSS, Bright, Applicable Materials: Alloy Steel