General description These heavy-duty TFHH5538 TechFast Hex Head Roofing Screws are specifically designed for fixing cladding and sheet steel to heavy section steel purlins. They are suitable for applications involving steel thicknesses between 6.0mm and 12.5mm. The screws feature a self-drilling tip for easy installation and a hex head for secure fastening, ensuring a durable and weather-resistant connection. Technical specifications Size: 5.5 x 38mm Pack quantity: 100 screws Finish: Elementech coating for corrosion resistance Head type: Hexagon Washer size: 16mm Material: Steel Compatibility and accessories Suitable for fixing cladding and sheet metal to heavy and light structural purlins Compatible with steel purlins between 6.0mm and 12.5mm thick Installation Use a compatible screwdriver or drill to drive the screw into steel or metal surfaces Ensure the rubber washer is properly compressed to form a weather seal Usage Ideal for roofing, cladding, and sheet metal applications in