IRWIN Tools 1888628 Impact Performance Series Concrete Screw Drill-Drive Installation Set for 1/4-Inch Screws, 4-Piece Built for maximum durability and long life with impact drivers Innovative pressed carbide tip with aggressive cutting angles for faster drilling and longer bit life One-piece construction withstands higher torque loads than standard quick-change bits Black oxide finish resists corrosion and increases life of bit 1/4" quick-change shank is designed to work with impact drivers, and reduces slipping in standard drill chucks