Hex Head Self Drilling Screw + EPDM Washer:5.5 x 65mm (2½") - DIN 7504K

This is a hexagon head self-drilling screw constructed with a built-in EPDM washer, designed for securing metal roofing and cladding materials. It conforms to the DIN 7504K standard, ensuring dimensional consistency and reliable performance for fastening applications. The 5.5mm nominal diameter and 65mm nominal length make it suitable for medium-thickness steel sheets where robust hold is required. Buyers select this format for its ability to penetrate and fasten in a single step, reducing installation time compared to traditional pilot hole methods. The integrated EPDM washer provides weather resistance, sealing the hole to prevent water ingress and protect the joint from corrosion. Choose this size based on the thickness of the substrate and the required clamping force for your specific roofing or siding project.