3 Hour Fire Rated Dampers

Combination Fire Smoke Dampers are UL 555 and UL 555S classified.

The 3 hour fire rated combination fire smoke dampers are used in walls, floors, or partitions with a fire resistance rating of more than 3 hours.

Class I leakage rating with airfoil blades, pressure up to 8 in. wg, velocity up to 4000 fpm, and temperature up to 350°F.