Star Brite Marine Silicone Sealant is true 100% marine-grade silicone to provide a durable, waterproof seal that will not crack, shrink or turn yellow. Retains flexibility for excellent adhesion to fiberglass, wood, glass, metal and some plastics. It is easy to apply and equally easy to remove when desired. Dries tack free in less than one hour, cures completely in 24 hours. Can be used above and below the waterline.