10"w X 28"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - [Outer Dimensions 11.75"w x 29.75"h] 12in diameter + Product Details Size –

+ Product Details Size – 25"w X 30"h is the size for the duct opening measurement only

+ Product Details Size – 26"w X 14"h is the size for the duct opening measurement only

actual front end outer dimensions are approximately 16 5/8" width X 18 5/8" height

+ Product Details Size - 18"w X 28"h is the size for the duct opening measurement only

10"w X 28"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - [Outer Dimensions 11.75"w x 29.75"h] 12in diameter + Product Details Size –+ Product Details Size 10"w X 28"h X 2"d (for duct opening measurement only); actual front end outer dimensions are 11. 75" Width X 29. 75" Height Weather and Pest Proof These louvers are especially designed to prevent water from entering your home, and with a built in back 1 2" mesh they also protect you from annoying rodents like mice, rats, birds, and squirrels High Quality Aluminum The premium durable aluminum will never rust and it will never