Complete hole drilling, tapping and deburring/countersinking in one operation with power drill saves labor and time. Back tapered beyond tap toprevent thread damage from over-drilling. Deburr/countersink also provided on bit beyond back taper/ Made from hardened high-speed steel vs. carbon steel forlonger life. High quality hex shank to ensure strong connection to drill chuck. Designed to tap up to 10-gauge metal.