Our dampers are manufactured from corrosion resistant ABS Engineering plastic. properties of this material prevent condensation making it ideal for use with heating/cooling air conditioning systems (temperature range 0- 65°C / 30-140 °F). Dampers serve as airflow capacity regulators in the ducts. They control the air supply to the individual users. These dampers are of the butterfly type and allow adjustment of 90° from fully open to closed position. 5 control methods are available: Mechanical, electrical, thermostat , remote control temperature Control, and R.F thermostat . The thermostatic method allows to control the dampers proportionally regarding the difference between the actual Room temperature and the desired temperature.