Irwin 10234 IRWIN Unibit High-Speed Steel Fractional Self-Starting Step Drill Bit, No.4 (10234)

10234. No.4. 3/16" - 7/8" Hole Sizes. 12 steps. 1/8" Maximum Material Thickness. High Speed Steel Fractional Self-Starting Features: Single-flute cutting edge for greater control through steps. Hex shank prevents slipping in drill chuck. Also available with (TiN) coating for longer life. New SpeedPoint tip penetrates faster than previous Unibits and prevents walking. Ideal for drilling holes into thin materials such as stainless steel, copper, brass, aluminum, plastic and laminates.