Description TOPCOAT® Sky-Lite is a clear, solvent-based synthetic rubber sealer designed to protect and waterproof porous, deteriorated fiberglass reinforced skylight panels. It is offered in a water-based version when flammability and VOC content are a concern. Uses Sky-Lite is specially designed to seal and rebind fiberglass mat or fiber used in the construction of skylight panels in addition to weathered plastic skylights. Sky-Lite protects and reconditions translucent fiberglass skylight panels found on roofs and walls. DO NOT use to repair cracked or broken skylight panels. DO NOT apply at temperatures below 42°F. Substrate temperatures must be below 120°F when applying product.