Backdraft damper, vertical or horizontal mount, Model WD-410, 10 In Sq, No Flange, Performance up to 2,500 ft/min

The WD-410 series are non-motorized backdraft dampers which may be mounted either vertically for intake air or mounted horizontally to allow vertical airflow down and prevent reverse airflow. The dampers are opened by air pressure differential and closed by springs.

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