Boss 125 Multi-Seal Building/Construction Sealant is a multi-purpose, one part sealant, formulated with USP Technology. This unique sealant is free from solvents and isocyanates. It cures on exposure to atmospheric moisture to form a highly durable flexible sealant. Boss 125 Multi-Seal has been formulated to offer outstanding primerless adhesion to most common building materials including vinyl, aluminum, steel, concrete, wood and glass. It can be applied and tooled under most weather conditions. This sealant is paintable with most latex base paints.