GEALAN-CAIRE® smart is installed on the side or top of your window. The airflow is between 4 to 40 m³ per hour. Exhaust and supply air flow through neatly separated channels. Two filters in class ISO Coarse 50% (optional ISO ePM25 70%) filter dust, pollen and other harmful particles and are easy to replace. A highly efficient heat exchanger minimises heat loss.