Flex Paste is a thick Paste that can be applied most surfaces, including under water and dries to flexible rubber. Coat, Seal and Protect. Super thick Rubberized Paste clings to surfaces and instantly fills gaps, cracks and holes. Expands and contracts and never shrinks. Paintable. Non Flamable, chemical and mildew resistant. Flex Paste clings to a wide variety of surfaces and will work on wood, glass, tile, concrete, aluminum, metal, brick, stucco, masonry, copper, fabric, fiberglass, ceramic, porcelain, natural stones, roofing, PVC, EIFS, EPDM, CSPE, Hypalon polyurethanes and more. Easy-to-use, making it a great option for crafts, hobbies, gardening and all types of projects.