14"w X 24"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - [Outer Dimensions 15.75"w x 25.75"h] Curved Blade Steel Actual Filter Size – 31 4 X 12 Is CRFG2028 Width_14in

Actual Filter Size – 31 3/4"w x 35 3/4" x 1"

actual front end outer dimensions are approximately 20 5/8" width X 30 5/8" height

actual front end outer dimensions are approximately 32 5/8" width X 34 5/8" height

+ Product Details Size - 36"w X 14"h is the size for the duct opening measurement only

but still very thin

14"w X 24"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace Weather Resistant Air Grille with Screen Mesh [Outer Dimensions 15.75"w x 25.75"h] Curved Blade Steel Actual Filter Size – 31 4 X 12 Is CRFG2028 Width_14in Actual Filter Size – 31 3 4"w x 35 3 4" x 1" actual front end outer dimensions are approximately 20 5 8" width X 30 5 8" height