Aluminum washers and plates to fix insulating panels.↵ 3320079 washers fix the panels with tapping or machine screws.↵ 3320080 Harpoon plates can be fixed with screws, fiberglass or epoxy glue. Panels are pierced by harpoon on which applies the 3320079 washer, then the harpoon is bented to fix the washer and the panel.