54 in Agricultural Wall Exhaust Shutter, 54-1/2 in x 54-1/2 in, DAYTON, Mfr# 45C668

57 In.H-W 5.75 In.L Aluminum Backdraft Damper, Damper Application Backdraft, For Nominal Duct Diameter Not Applicable, Frame Material Aluminum, Number of Panels 2, Maximum Air Velocity 2500 fpm, Overall Height 57 in, Rough Opening Diameter 54 1/2 in, Rough Opening Shape Square, Fits Fan Diameter 54 in, For Duct Shape Not Applicable, Free Area 16.7 sq ft, Overall Width 57 in, Frame Material Thickness 20 ga, Overall Length 5 3/4 in, Connection Type Not Applicable, Frame Depth 2 1/4 in