Rust-Oleum® LeakSeal® Flexible Rubber Coating is an easy to use, rubberized protective utility coating designed to fill gaps & cracks up to 1/4” and seal out water, air & moisture. It provides a watertight, weatherproof barrier that also protects the surface from rust. LeakSeal dries to a semi-smooth, firm finish that will not sag or drip, and can be top-coated with latex or oil based paints. Designed for use on metal, aluminum, galvanized metal, PVC, concrete, masonry, asphalt roofing materials, vinyl, fiberglass, and more. Not recommended for rubber surfaces or surfaces exposed to continuous water immersion.