Shockwave Impact Duty Insert Bits are engineered for extreme durability and up to ten times life. Made from proprietary steel and heat treated to control hardness, these insert bits feature an innovatively designed geometric shock absorption zone to extend life. The forged tip allows for a secure grip and maximum contact eliminating stripping or slipping. Assorted 1″ insert bits includes 1 each: T10, T15, T20, T25, T27, T30, T40.