Louver Damper, Adjustable, 42H x 30W

44.5 In.H 32.5 In.W Drnbl Extrd Alu Combo Dmpr, Louver Type Combination, Frame Type Flanged, Outside Height 41 1/2 in, Outside Width 29 1/2 in, Rough Opening Height 42 in, Rough Opening Width 30 in, Louver Maximum Intake 4,075 cfm, Maximum Exhaust 5,827 cfm, Flange Width 1 1/2 in, Free Area 3.6 sq ft, Beginning Point of Water Penetration 1,118 fpm, Maximum Air Velocity 3,000 fpm, Blade Angle 45 Degrees , Material Aluminum, Inside Height 40 1/2 in, Inside Width 27 3/4 in, Number of Blades 9