Louver Damper Adjustable 54H x 36W

56.5 In.H 38.5 In.W Drnbl Extrd Alu Combo Dmpr Louver Type Combination Frame Type Flanged Outside Height 53 1/2 in Outside Width 35 1/2 in Rough Opening Height 54 in Rough Opening Width 36 in Louver Maximum Intake 6 614 cfm Maximum Exhaust 9 457 cfm Flange Width 1 1/2 in Free Area 5.9 sq ft Beginning Point of Water Penetration 1 118 fpm Maximum Air Velocity 3 000 fpm Blade Angle 45 Degrees Material Aluminum Inside Height 52 1/2 in Inside Width 33 3/4 in Number of Blades 11