Bio-Kleen Fiberglass Cleaner is a boat, RV, camper and trailer exterior cleaner. Designed to dissolve and remove rust, scale, lime, corrosion, soap scum, chalking, yellow stains from a fiberglass RV and most water minerals from fiberglass and acid resistant surfaces including: raw metals, porcelain, tile and grout. Rapid action quickly penetrates mineral buildup and dissolves in minutes. Leaves surface sparkling clean. Use on boat hull, drives, props, pontoons, trailers, fiberglass RV exterior, campers, tires, wheels, rims, metals, sinks, bathtubs, shower stalls, toilet seats and bowls, stainless steel fixtures, swimming pools, ceramic tiles and grout.