Combination Louver Damper 54x54

54 In.H 54 In.W Drnbl Extrd Alu Combo Dmpr Louver Type Combination Frame Type Hat Channel Outside Height 53 1/2 in Outside Width 53 1/2 in Rough Opening Height 54 in Rough Opening Width 54 in Louver Maximum Intake 5 950 cfm Maximum Exhaust 9 350 cfm Flange Width Not Applicable Free Area 8.5 sq ft Beginning Point of Water Penetration 1 118 fpm Maximum Air Velocity 3 500 fpm Blade Angle 45 Degrees Material Aluminum Inside Height 52 1/2 in Inside Width 51 3/4 in