Overview Reviews Product Description Get it all done with one when you choose Unibit® stairstep bits.Single-flute cutting edge provides precise depth control though all size steps.Shanks flat side surface ensures slip-free chuck lock-down.Blunt-tip, hole-enlarging bit may be used on stainless steel, copper, brass, aluminum, plastic, laminates and wood.Materials: steel drill bit range min: 1/2 drill bit range max: 1. Irwin Tools Catalog Product Videos Custom Field Manufacturing country US Product Reviews Write a Review Write a Review × Irwin UNIBIT® 9/16 - 1" #20 High Speed Steel Step Drill Bit 10220 Rating * Select Rating 1 star (worst) 2 stars 3 stars (average) 4 stars 5 stars (best) Name Review Subject * Comments *