IRWIN Tools 1870569 Impact Performance Series Concrete Screw Installation 3/16-Inch X 6-Inch Drill Bit for 1/4-Inch Screws 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