Greenlee Standard 7-Piece Drill/Tap Bit Sets Complete hole drilling, tapping and deburring/countersinking in one operation with power drill. Back taper beyond tap to prevent thread damage from over-drilling. Deburr/Countersink also provided on bit beyond back tape. Made from high-speed steel vs. carbon steel for longer life. High quality hex shank to ensure strong connection to drill chuck Pack of 1