The Irwin Tools 4935641 1/4-Inch Black Oxide Hex Shank Drill Bit is a 2-piece Black Oxide drill bit designed to work with todays 1/4-Inch quick change chucks and extensions. The Black Oxide Hex Shank High Speed Steel drill bits feature a 135-Degree split-point tip for faster starts with no -Inchwalking.-Inch They're manufactured with premium high speed steel with a black and gold oxide coating for major corrosion resistance. This bit works in quick change impact drivers and because it has a quick change shank, you can change from drilling to driving quickly to get the job done fast.