Low to high velocity, non-toxic adhesive-seaant for permanently sealing the fabricated joints and seams of sheet metal air ducts, UL-181 listed rigid fiberglass air ducts, UL-181 listed flexible air ducts and thermal insulation. Also ideal for repairing damaged and leaking air ducts and sealing conditioned spaces from air infiltration. Waterbased, non-flammable, high solids content, fiber reinforced, excellent longevity (actually strengthens with age), fire/mold/mildew resistant, weatherproof, elastomeric. Easy to apply and clean up.