They allow airflow to pass in one direction and to stop it in the other route. They can be produced from corrosion resistant extruded aluminum. A steel grille installs more than and absolutely conceals the mounting tabs for any cleanse, aesthetic finish. The fireplace damper is offset from the sleeve https://dampers-for-industrial-se46778.answerblogs.com/37263830/a-review-of-dampers-for-industrial-sector