Designed to enhance the strength and longevity of seals created with FlashSeal Flexible Flashing Sealant. Extra reinforcement is vitally important in chimney flashing. Leaks and floods can damage not only your chimney but the interior of your home, too. That is why our FlashSeal fabric is one of our best sellers- homeowners realize the importance of reinforcing their chimneys. The FlashSeal fabric serves as a layer between the base coat and top coat of FlashSeal. The fabric comes in 6" X 150" rolls, enough to do several crowns.