Hex Head Self Drilling Screw + EPDM Washer:5.5 x 20 mm (¾") - DIN 7504K

This fastener is a hexagon head self-drilling screw measuring 5.5 mm in nominal diameter and 20 mm in nominal length, manufactured to the DIN 7504K standard. It features an integrated EPDM washer designed to create a weather-tight seal at the fastening point. The self-drilling tip allows for direct installation into steel sheets without a pre-drilled pilot hole, which significantly reduces installation time compared to standard screws. Buyers typically select this specific combination when working with thin-gauge metal roofing or cladding, as the EPDM washer provides necessary corrosion protection and sealing against water ingress. Choose this size when a 20 mm penetration depth is required to secure structural members or profiles, ensuring the selected diameter aligns with your substrate thickness requirements.