Greenheck’s HB Series of heavy duty industrial backdraft dampers has grown with the addition of the HBR-150, a round industrial backdraft damper with a flanged-style frame. The HBR-150 is rated for velocities up to 4,000 fpm and back pressures up to 6-inch wg. Backdraft dampers are designed to allow airflow in one direction and prevent reverse airflow. Greenheck officials said the HB Series industrial backdraft dampers feature counterbalance weights that are mounted externally for easy adjustment and balancing in the field. HB Series dampers are recommended for low temperature, clean air applications such as in blower outlets, branch duct isolation, and industrial process isolation.