If you work with fiberglass, manmade stone, composites, fiber cement board, or light gauge steel studs, you are really going to appreciate these screws when you need corrosion resistance. Until now, the only screws available had Phillips recesses, which forced a choice between corrosion resistance and drivability. Well, there is no need to settle anymore. These have a #2 self drilling point which when used with light gauge steel is designed for a total material thickness of .035 to .100. In softer materials like fiberglass the material thickness can be ignored. Made in Taiwan.