Dayton Drainable Louver,Fixed,17-1/2 H,Alum 5NKJ2

18 In.H 18 In.W Drnbl Extrd Alu Intake Louver, Louver Type Stationary Blade, Frame Type Hat Channel, Frame Depth 4 in, Mounting Style Recess Mount, Outside Height 17 1/2 in, Outside Width 17 1/2 in, Rough Opening Height 18 in, Rough Opening Width 18 in, Louver Maximum Intake 744 cfm, Maximum Exhaust 1,063 cfm, Maximum Outside Width 17 1/2 in, Minimum Outside Width 17 1/2 in, Flange Width Not Applicable, Free Area 0.9 sq ft, Beginning Point of Water Penetration 1,031 fpm