Model D1201-OW and D1201-DOW are "out of wall" high performance dynamic fire dampers. They offer premium performance and a low pressure drop well suited to the majority of commercial applications. Unique, inter-locking double skin blade design eliminates combustible seals and provides flame protection under fire conditions at temperatures up to 2000°F (1366°C). Model D1201-OW design allows for through the grille access to the damper actuator and other components.  Model D1201-DOW is ideal for applications where the damper cannot be installed with the plane of the wall or floor.