20ga galvanized steel frame for dampers <10" diameter
16ga galvanized steel frame for dampers >11" diameter
Designed with constant force springs in the horizontal configurations to ensure closure under airflow conditions. Can also be used in static system applications.
Meets all UL and NFPA requirements for Primary Fire Dampers, and carries a UL555 classified fire damper label.
Approved for use where ducts penetrate partitions with fire resistance ratings of two hours or less.
1-1/2 hour rating for use in fire barriers rated two hours or less.