Aoibox 24 in. 1400 RPM, 2750 CFM High-Speed Aluminum Gable Mount Attic Fan Shutter Exhaust Fan in Silver (1-Pack)
The shutter exhaust fan is perfect for removing excess heat, moisture, dust and odors from virtually any residential or commercial space. Applications include workshops, welding rooms, factories, warehouses, barns and greenhouses. This wall-mounted exhaust fan includes automatic gravity shutters that open and close in conjunction with the operation of the fan. The completely enclosed motor is thermally protected and permanently lubricated. Color: Silver.

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