Louver Damper, Adjustable, 54H x 24W, DAYTON, Mfr# 20UA97

56.5 In.H 26.5 In.W Drnbl Extrd Alu Combo Dmpr, Louver Type Combination, Frame Type Flanged, Outside Height 53 1/2 in, Outside Width 23 1/2 in, Rough Opening Height 54 in, Rough Opening Width 24 in, Louver Maximum Intake 4,209 cfm, Maximum Exhaust 6,018 cfm, Flange Width 1 1/2 in, Free Area 3.8 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 21 3/4 in, Number of Blades 11