Fusor® 129 controlled flow sealer is a two-component, epoxy-based seam sealer used for duplicating factory appearance on roof channels, door seams, drip rails, trunk seams and truck bed floor seams. Fusor 129 seam sealer is fast curing and bonds extremely well to painted and two-component primed surfaces. Sealer can be applied directly to bare metal on rigid joints, however flexible joints, such as roof seams and drip rails, should always be primed.