Meguiar's Boat and RV Polish and Gloss Enhancer restores brilliant gloss on fiberglass and painted marine or RV surfaces after cleaning. It is specially formulated to provide valuable oils that feed and nourish the fiberglass or painted surfaces. Meguiar's Boat and RV Polish and Gloss Enhancer is especially effective on dark colors. NOTE: Use polish only after the surface has been cleaned and restored to a "like new" or "average" finish.