The following video will demonstrate the performance of a constant airflow regulator and a fixed opening. For this demonstration, a 35 cfm CAR-II constant airflow regulaor and a fixed orifice plate that was designed to achieve 35 cfm at 0.2″w.g. were selected. Some claims have suggested that a fixed opening size (an orifice plate, grille, or balancing damper) is a low-cost way to regulate airflow. These claims oppose the use of manufactured solutions like constant airflow regulators. A side-by-side comparison of a fixed opening and a constant airflow regulator dispels these claims.