CENTRIC AIR Gable Attic Fan. Ultra Quiet. Energy Efficient. Plug and Play. Fully Assembled. Thermostatically Controlled. Rated for 40,000-Hours of Operation. German engineered, 5 blades, acoustically designed, precision balanced fan made of composite materials with wingtips makes for an ultra quiet operation with virtually no vibration. Custom sheet metal box allows for easy installation and maximum airflow through the gable vent for increased efficiency. Sealed motor prevents dirt and debris from plugging the motor, contributing to premature failure.