This roof coating system for fiberglass roofs on RVs from Dicor provides a 100% acrylic resin coating that forms a flexible layer over any fiberglass roof to protect and beautify. Dicor Fiberglass RV Roof Coating gives roofs a superb finish that while reflecting the sun's heat to keep the interior cooler. Always use Dicor Fiberglass Clean & Prep before applying the coating finish to your roof. This helps ensure proper adhesion of Dicor Fiberglass RV Roof Coating to a fiberglass roof. It is specifically formulated to remove all wax, oils, road grit, and other impurities on gel coat and to enhance the adhesion of the roof coating. The fast acting formula is also biodegradable and very easy to use. Contains 1 gallon.