Bio-Kleen M00605 Fiberglass Cleaner, 16 oz.Removes chalking, algae, rust, scale, lime, corrosion, and light oxidation from boats. Removes chalking and light oxidation from a fiberglass RV exterior. Easily removes built up mineral deposits on outdrives and thru-hull boat exhaust. A clinging spray-on gel that sticks, increasing surface penetration and dwell time. Use on boat hull, drives, props, pontoons, fiberglass RV exteriors, trailers and campers, tires, wheels, rims, metals, sinks, bathtubs, shower stalls, toilet seats, bowls, stainless steel fixtures, swimming pools, ceramic tiles and grout. Biodegradable.