The Horizon Tunnel Door Ventilation System from Munters Corporation uses closed cell insulated foam doors with a molded fiberglass exterior that provides R-value and rigidity to weight ratio. Features include: custom designed actuator, rack and pinion system, and multi-row control using a single actuator. The door uses a closed cell foam which offers 30% additional R-value. Also, the doors open to near 90 degrees for maximum airflow. 

The Horizon Tunnel Door Ventilation System is designed for easy assembly with welded bracketry, minimum fasteners and minimum adjustments.