Combination Louver Damper,12x12
3 sq ft, Beginning Point of Water Penetration 1,118 fpm, Maximum Air Velocity 3,500 fpm, Blade Angle 45 Degrees , Material Aluminum, Inside Height 10 1/2 in, Inside Width 9 3/4 in, Number of Blades 2.W Drnbl Extrd Alu Combo Dmpr, Louver Type Combination, Frame Type Hat Channel, 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 131 cfm, Maximum Exhaust 206 cfm, Flange Width Not Applicable, Free Area 0.H 12 In.