Thompson's WaterSeal Heavy Duty Deck Cleaner is formulated to remove weathered clear and tinted waterproofers, as well as semi-transparent stains from exterior wood surfaces. It restores the natural color of severely weathered and discolored wood without bleaching. This self-neutralizing cleaner eliminates the need for an additional solution before waterproofing or staining. It effectively removes stains from dirt, mildew, algae, and fungus, and is ready to use straight from the container. Ideal for decks, fences, outdoor furniture, and composite decking, it prepares surfaces for waterproofing. The cleaner brings back the wood's natural color and beauty.