The FSD35 Combination Fire/Smoke Damper is both UL555 and UL555S Classified. It is rated as a 1-1/2 hour fire damper and a Leakage Class III Smoke damper. It features:
- Triple vee groove blades.
- Rated to 2,000 fpm and 4" w.g.
- UL approval for dual directional airflow.
- Failsafe design, which enables the damper to automatically assume the desired position when fire or smoke (if smoke detector is present) interrupts operational power.
- The EFL or PFL heat-actuated release devices permit controlled closure through the actuator and are automatically remote resettable after test, smoke detection, or power failure conditions.
- Galvanized steel construction