Products Architectural Louvers, Dampers, Roof Curbs, Actuators, Grilles, Sunshades and more. Dampers - Backdraft Dampers: Model:HCB-700 Heavy Duty Rectangular Damper up to 4" w.g. APPLICATION The Model HCB-700 is a vertical or horizontal mounted backdraft damper that is designed to allow vertical or horizontal airflow and prevent reverse airflow. HCB-700 DOCUMENTS - Submittal Sheet - HCB-700 BIM (REVIT) Drop Plenum Diffusers Balancing / Regulating Dampers UV Products Iris Dampers Louvers Dampers UL Listed Dampers Roof Curbs and Rails Sunshades Architectural Grilles Ventilators Doors Actuators Fans Air Measuring Products VAV Terminals Security Bars & Grilles Plenums Duct Take-Offs Custom Work Manufacturer Cross Referencing System View Now Previous Next