12 In.H 12 In.W Drnbl Extrd Alu Intake Louver Louver Type Stationary Blade Frame Type Hat Channel Frame Depth 4 in Mounting Style Recess Mount Outside Height 11 1/2 in Outside Width 11 1/2 in Rough Opening Height 12 in Rough Opening Width 12 in Louver Maximum Intake 144 cfm Maximum Exhaust 188 cfm Maximum Outside Width 11 1/2 in Minimum Outside Width 11 1/2 in Flange Width Not Applicable Free Area 0.4 sq ft Beginning Point of Water Penetration 1 031 fpm