Rust-Oleum wet or dry roof repair roof cement is a fibered, asphalt based cement that provides a strong and flexible seal and resists cracking. Ideal for installing or repairing roof flashings at valleys, parapet walls, gravel stops, stacks, vents, monitors and similar applications. Also suitable for sealing cracks in exterior foundation and chimney walls. It is perfect for use with fiberglass or polyester fabric or roll roofing for permanent repairs. Rust-Oleum wet or dry roof cement applies fast and smooth without stringing.