Constant Volume Regulators (CVRs) limit airflow to a maximum value across its effective range. They are used for both supply and return applications when the designer wants a consistent volume of air to be added or removed from the space. Toilet and kitchen exhaust, Outside Air, and Makeup air are all common applications.
CVRF5 has been designed primarily as a deeper register wall enclosure to accommodate both the CVR and a Dynamic Fire Damper. (They can be fitted with Ceiling Radiation Dampers as well) It is a back exit box.