EFS Multi-Blade Combination fire and smoke damper is rated as a 3 hour fire damper and a Leakage Class I Smoke damper for up to 350°F. For use in dynamic systems, per SI 1001 part 3 (UL 555) and SI 1001 part 4 (UL 555S).

As a life safety fire damper, it has a failsafe design which enables the damper to automatically close upon the detection of heat and/or loss of power. The electric heat responsive device enables controlled closure through the actuator and is automatically remotely reset after testing, smoke detection, or power failure conditions.

EFS damper provides a low pressure drop design, qualified to 2,000 fpm (10.2 m/s) and 4.0 in. WC (1.0 kPa) and can be installed in vertical walls and partitions, or horizontally in floors or assemblies with fire resistance ratings up to 4 hours.