Lutra Tools - Step Drill Bit Set - 3 Piece Set with Pouch | Titianium Coated HSS Steel HEX Shank Automatically Deburrs Holes as you Drill Two-flute Design Gives You Faster, Smoother Cutting Titanium Nitride Coating for Cooler Running Quick-change 1/4" Hex Shank These Step Drill Bits are ideal for variety of materials from metal, plastic, fiberglass to wood