General description The Concrete Frame Screws are self-tapping, made from hardened zinc-plated steel, designed for easy installation into concrete or masonry. This pack of 100 screws features a durable head that resists stripping, ensuring reliable performance even under resistance. They are ideal for fixing window and door frames securely to masonry or concrete walls. Technical specifications Size: 7.5mm x 72mm Recommended screw diameter: 6.5mm Material: Galvanized alloy steel Usage Designed for fastening window and door frames to masonry or concrete walls. Can also be used with roofing applications. Other information The zinc plating provides temporary protection against rust; however, once worn, the steel may rust.