Referred to as the "multi-material construction screw", SPAX screws can be used in concrete, sheet metal, drywall, particle board, cement board, and even plastic materials. These patented screws have a phillips/square combination drive for excellent torque, and are available with a high corrosion resistant Teflon -like heat resistant galvanized coating, Dacromet, which passes an 800 hour salt spray test. No pre-drilling is required in most materials. They will not break. SPAX screws are an instant solution for almost any construction project.