10"w X 18"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - [Outer Dimensions 11.75"w x 19.75"h] w10h10 + Product Details Size –

+ Product Details Size – 34"w X 14"h is the size for the duct opening measurement only

+ Product Details Perfect Fit & Easy Sizing - Designed for a 18" x 24" OR 24" x 18" duct opening (measured at the opening)

+ Product Details Size – 28"w X 36"h is the size for the duct opening measurement only

+ Product Details Size – 8"w X 20"h is the size for the duct opening measurement only

10"w X 18"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - [Outer Dimensions 11.75"w x 19.75"h] w10h10 + Product Details Size –+ Product Details Size 10"w X 18"h X 2"d (for duct opening measurement only); actual front end outer dimensions are 11. 75" Width X 19. 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