Automatic Shutter - Broan 433
The Broan Automatic Shutter allows for more air movement than conventional stationary attic louvers. Counter-balanced aluminum vanes open automatically on the attic fan when ventilator is turned on and close when attic fan stops. The Broan Automatic Shutter flange fits flush against outside wall for neat, smooth appearance. Reinforced for strength; the attic fan provides weather tight closure.
(Use With Models 353 And 35316 - Sold Separately)