The Irwin Impact Screwdriver Bits are specifically designed for use in high torque impact drivers. They are manufactured from heavy-duty, high-grade steel and have a 3 times increased life compared to standard screwdriver bits. Their precision tip geometry delivers superior fitment, reducing stripping and cam-out. The bits are Power Groove designed for compatibility with IRWIN Impact Performance Series™ magnetic screw-hold attachment. This set contains the following:7 x 25mm Phillips Bits: PH1(x2), PH2(x3) and PH3(x2).7 x 25mm Pozidriv Bits: PZ1(x2), PZ2(x3) and PZ3(x2).7 x 25mm TORX Bits: T20(x3), TX25(x2) and T30(x2).5 x 50mm Phillips Bits: PH2.5 x 50mm Pozidriv Bits: PZ2.1 x 3in Bit Holder. Supplied in a moulded ABS resin case.