Super-thick, rubberized Flex Seal Flex Paste provides powerful performance, ensuring effective and reliable results with every use. Perfect for filling large gaps, cracks and holes, powerful paste creates a strong, flexible and waterproof seal. It is also ideal for sealing out rodents and pests, foundation repairs, bath and shower repairs, roof repairs, and many other types of projects - both indoors and outdoors. Specialty paste creates sealing barriers on many various surfaces, including: wood, glass, tile, concrete, aluminum, brick, stucco, metal, fabric, ceramic, porcelain, roofing, PVC, EPDM and much more. Flex Paste begins to cure once exposed to air, moisture and humidity, and it will skin in 15-30 minutes. Allow each coat to dry before applying additional coats. It will cure in 24-48 hours and gets stronger over time for more effective, longer-lasting repairs.