Vulkem 116 Limestone Polyurethane Window and Door Caulk Sealant is a high-performance, single-component sealant formulated for sealing joints around windows, doors, siding and other exterior openings. It cures to a durable, flexible elastomer that resists weathering, UV exposure, and moisture intrusion while accommodating joint movement. Designed for professional and DIY use, this caulk bonds strongly to common construction materials like wood, metal, masonry and vinyl without primer in many cases. With a smooth application and excellent tooling characteristics, Vulkem 116 delivers a long-lasting, waterproof seal that helps improve energy efficiency and protects structures from air and water leaks in a range of climates.