54 in Backdraft Damper / Wall Shutter, 54-1/2 in x 54-1/2 in, DAYTON, Mfr# 3C115

57 In.H-W 6 1/4 In.L Alum Wall Fan Shutter, Damper Application Backdraft, For Nominal Duct Diameter Not Applicable, Frame Material Galvanized Steel, 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 17 sq ft, Overall Width 57 in, Frame Material Thickness 20 ga, Overall Length 6 1/4 in, Connection Type Not Applicable, Frame Depth 2 1/2 in