Gellert’s Ruskin® Backdraft Exhaust Dampers are gravity operated and open with air flow and pressure. Backdraft design prevents air from entering the building through the Exhaust Dampers. Damper blades are constructed from .050” thick extruded aluminum with extruded vinyl blade edge seals and are mounted in an aluminum frame with synthetic bearings. Gellert’s Ruskin® Backdraft Exhaust Dampers provide high performance with minimal maintenance to guarantee a long operational life.