Dayton Intake Louver,Fixed, Drainable,30H x 30W 20UA11

33 In.H 33 In.W Drnbl Extrd Alu Intake Louver, Louver Type Stationary Blade, Frame Type Flanged, Frame Depth 4 in, Mounting Style Surface Mount, Outside Height 29 1/2 in, Outside Width 29 1/2 in, Rough Opening Height 30 in, Rough Opening Width 30 in, Louver Maximum Intake 3,256 cfm, Maximum Exhaust 4,656 cfm, Maximum Outside Width 32 1/2 in, Minimum Outside Width 32 1/2 in, Flange Width 1 1/2 in, Free Area 3.2 sq ft, Beginning Point of Water Penetration 1,031 fpm, Maximum Air Velocity 3500 fpm