Treat your spa tub or hot tub shell with care, and it will contribute to a bright and shining hot tub experience. The shell of your spa or hot tub is constantly exposed to water and chemicals, so it must be protected and maintained to prevent breakdown. Application of Fast Gloss from Leisure Time waterproofs, seals, shines, protects and prevents fading and oxidation for hot tub and spa shells of all materials. Dry the spa shell, then spread Fast Gloss evenly across the surface with a sponge. Let it dry for 10-15 minutes, then wipe and buff with a clean cloth. Repeat as desired until your shell is as bright and shining as the day you bought it.