#8 x 1 5 8" Phillips Wafer Cement Board Screw Dagger Guard Coating, Pkg 4000 Wood to Metal Self Drilling Screws Floor loads may be adjusted Floor loads may be adjusted for other load durations according to the code and homeowners create stronger roof framing systems that perform reliably in demanding weather conditions The proprietary Dagger Guard coating passes the 1000 hour salt spray test and provides excellent corrosion resistance that's suitable for exterior applications 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