Step Drill Bit Set, High Speed Steel, Black Oxide, 1/8 in to 1/2 in, 13/16 in to 1 3/8 in, 3/16 in to 1/2 in, 3/16 in to 7/8 in Size Range, Straight with Three Flats, Number of Drill Bits 3, Shank Hex Size 1/4 in, 3/8 in, 7/16 in