#5 Unibit, 1/4" To 1-3/8" Step Drill, 10 Hole Sizes From 1/4" To 1-3/8" In 1/8" Increments, Maximum Material Thickness 1/8", 3 Flatted Shank, Shank Size 1/2", Single Fluted Cutting Edge Assures True Round Holes & Allows Greater Control, Carded.