Safecoat AFM DynoFlex is a unique, water based, low odor elastomeric sealer that comes in a paste-like compound for sealing seams, joints and cracks in new and old heating and air conditioning ducts, and for repairing metal roofs and asphalt shingles. Also comes in a sprayable form that can be used over Safecoat DynoSeal as a topcoat for roofs and decks.