Dec-Smart galvanized base with PrimeGuard Plus coating finish. Flat counter sinking head. Combo drive, extra coarse thread screws with high corrosion-resistant, long life coating. The screw color is similar to the color of treated wood. Compliant for treated lumber. Type 17 drill tip drives into wood without pre-drilling. Thread pattern reduces wood splitting and friction. For all exterior applications, including decks, docks, fences, and gazebos.