Irwin #1 Unibit Self-Starting Stairstep Bit, 13-Step, 1/8" to 1/2" Dia, 1/8" Depth: * Drill a range of holes without changing bits when you equip with a stairstep bit * SpeedPoint tip penetrates quickly and cleanly without the walking issues common among alternative point designs * Patented single-flute edge provides precise depth control though all size steps * Hex-shaped shank enables secure, slip-free lock down * Self-starting bit may be used on stainless steel, copper, brass, aluminum, plastic, laminates and wood * Material(s): Steel * Drill Bit Range (Min): 1/8" * Drill Bit Range (Max): 1/2"