Daggerz™ brand self-drilling cement board screws are a high quality screw designed for cement-board to metal fastening jobs. These screws are designed to anchor cement board to wood or 25-20 guage metal studs and the wafer head has nibs on the bottom allowing the screw to countersink flush into the cement board. The proprietary Dagger-Guard coating passes the 1000 hour salt spray test and provides excellent corrosion resistance that's suitable for exterior applications.