This screw is specially designed with a large hex flange head and a single black washer. The threads feature a high-low thread pattern with a Type 17 cutting point at the tail. The single black washer provides effective waterproofing and leak prevention. To enhance corrosion resistance, we have improved the surface treatment by applying a high-strength Dacromet coating, offering 500 to 1000 hours of salt spray resistance, which significantly reduces rust and extends the screw’s service life.
The high-low threads improve working efficiency and ensure a tight connection—high threads are responsible for cutting, while low threads lock the material securely in place. The Type 17 tip is specially designed to quickly expel wood chips during installation.
Popular applications include roofing and metal construction, with common sizes such as 5/16 hex head self tapping screws, 3/8 hex head self tapping screws, and 50mm roofing screws. These screws are ideal for metal roof installation.
If you have any needs, please feel free to contact us. We look forward to the opportunity to cooperate.
