Self drilling T17 gash point screw with hex head and EPDM washers. Used for joining metal roofing panels to timber frame buildings. Salt spray tested to 1000 hours. Use these TechFast roofing screws for joining metal roofing panels to timber frame buildings. No pre-drilling is needed - the self-drilling T17 Gash Point ensures a rapid insertion, while an Elementech anti-corrosion coating offers durability. Roofing screws for joining metal roofing panels to timber frames. Self-drilling with 8mm hex head and 16mm EPDM washer. T17 Gash Point for a rapid installation - no pre-drilling. Suitable for a steel thickness of 0.5-1.2mm. Elementech coating for superior anti-corrosion. Salt spray-tested to 1,000 hours. TechFast Sheet To Timber Hex/Washer Roof Screw 6.3 x 125mm (50 Pack) in Silver Steel. Forgefix TechFast Metal Roofing Panels to Timber Hex Screws are used to join metal roofing panels to timber frame buildings. They have a specially designed compression control thread to prevent damage and denting of panels. No pre-drilling is required and the self-drilling T17 Gash Point on screws makes for a rapid installation. The nails are fire and corrosion resistant, protected by Elementech corrosion resistant coating, salt spray tested to 1000 hours. Complies with EU Safety, Health and Environmental requirements. They are supplied with 16mm EPDM rubber washers. These Forgefix TechFast Metal Roofing to Timber Screws have the following specification: Size: 6.3 x 125mm Steel Thickness: 0.5-1.2mm Head Type: 8mm Hex Pack Size: 50.