20"w X 28"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - [Outer Dimensions 21.75"w x 29.75"h] w22h22 + Product Details Size – 4 X 12 Is CRFG2028 Width_14in

+ Product Details Size – 14"w X 8"h is the size for the duct opening measurement only

75" width X 17

actual front end outer dimensions are approximately 22 5/8" width X 32 5/8" height

+ Product Details Size – 32"w X 10"h is the size for the duct opening measurement only

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

20"w X 28"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace Weather Resistant Air Grille with Screen Mesh [Outer Dimensions 21.75"w x 29.75"h] w22h22 + Product Details Size – 4 X 12 Is CRFG2028 Width_14in + Product Details Size – 14"w X 8"h is the size for the duct opening measurement only 75" width X 17