DYNAFLEX ULTRA Advanced Exterior Sealant for Windows, Doors, Siding & Trim is powered by innovative WEATHER MAX Technology for long-lasting, All Weather Protection. It provides exceptional UV resistance against color fading, yellowing, cracking, chalking and crumbling so the sealant stays looking new.Once cured, DYNAFLEX ULTRA resists mold, mildew and algae for the life of the sealant. The tough surface resists dirt build-up and water absorption for a durable, 100% waterproof seal that stands up to the elements. It has strong multi-material adhesion and stays permanently flexible to endure expansion and contraction caused by sun, heat, cold, wind and rain. It is rain and paint ready in one hour to save time and provide better productivity. Easy to gun out for less fatigue and smooth tooling for a better finish.