This automatic shutter has counter-balanced aluminum vanes that open automatically when ventilator is turned on and close when the fan stops. It allows more movement than conventional stationary attic louvers. The flange fits flush against the outside wall for a neat, smooth appearance and the unit is reinforced for strength.
- Made of extruded aluminum with felt on edges
- Use with 16", 14" and 12" fans
- 16-1/4" I.D.; 19-1/16" O.D.
- Instructions included
- Weight: 4.7 lbs.