DFD-350
Model DFD-350 is for use in walls, floors, and partitions with fire-resistance ratings of three hours or more. This model has a 3¹¹/₁₆ inch frame. Dynamic-rated-fire dampers are used with HVAC systems that remain operational during a fire emergency. Pressure: Up to 4 in. wg Velocity: Up to 4000 fpm