IRWIN 1903514 Impact Performance Series Double-Ended Screwdriver Power Bit Set with Magnetic Screw Hold, Number 2 Square, 2 3/8-Inch, 4-Piece Built for maximum durability and long life with impact drivers ensures both ends of bit lock securely in impact drivers and quick-change chucks, enabling use of two tips from one bit Precision tip geometry delivers superior fitment, reducing stripping and cam-out Power Groove designed for compatibility with IRWIN Impact Performance Series Magnetic Screw-Hold Attachment 1/4" quick-change shank is designed to work with impact drivers and reduces slipping in standard drill chucks