IRWIN IRW1923436 Impact Screwdriver Bit Set of 22 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 Phillips bits: PH1 x 2, PH2 x 4 and PH3 x 1. 7 x Pozi bits: PZ1 x 2, PZ2 x 4 and PZ3 x 1. 7 x Torx bits: T20 x 4 and T30 x 3. 1 x Magnetic Screw Bit Holder Attachment Supplied in a moulded ABS resin case.