Master Flow 24" Whole House Attic Exhaust Fan Direct Drive 4500 CFM w/ Shutter
The GAF Master Flow 4500 CFM 24 in. A minimum 1100 sq. ft. of attic space with a minimum of 1008 sq. in. of net free area attic exhaust is required for proper operation. 4500 CFM 24 In. Direct Drive Whole House Fan With Shutter.