Henry 481 Stop Leak 100% Silicone Spray Sealer is a premium, easy-to-use, 100% silicone aerosol leak sealer, formulated to provide a permanent leak-proof seal on a variety of surfaces. This multi-purpose leak sealer waterproofs and protects gutters, skylights, flashing, roofs, RVs, campers, windowsills, foundations, boats, cars, concrete, glass, metal and more.