Zinc plated. These Forgefix single thread Coach Screws are designed for strong, heavy-duty fixing when working with timber. They are tough, reliable, and easy to use with a sharp tip and coarse thread for a firm and secure fit. The traditional hexagon head allows for greater torque with a socket driver. Perfect for fixing to timber in fencing and joinery applications. Zinc-plated for increased corrosion resistance and durability. Conforms to DIN 571 standards. Applications include heavier timber installations, fixing timber to masonry, and satellite dish installations with wall plugs. Zinc coatings prevent oxidation and protect the metal.