Neiko Tools U.S.A. Titanium Step Drill Bit 1/4" to 1-3/8" in 1/8" Increments, Two-Flute Design for Faster, Smoother Cutting, 3 Flatted 3/8" Shank, Heat Treated HSS with Titanium Nitride Coating, Self-starting - no walking and no center punch required, Perfect for clean holes in thin materials like steel, stainless steel, copper, aluminum or plastic