28"w X 6"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - [Outer Dimensions 29.75"w x 7.75"h] Adjustable Return ensuring a perfect fit

ensuring a perfect fit

+ Product Details Size – 24"w X 20"h is the size for the duct opening measurement only

actual front end outer dimensions are approximately 38 5/8" width X 8 5/8" height

+ Product Details Size – 18"w X 8"h is the size for the duct opening measurement only

28"w X 6"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - [Outer Dimensions 29.75"w x 7.75"h] Adjustable Return ensuring a perfect fit+ Product Details Size 28"w X 6"h X 2"d (for duct opening measurement only); actual front end outer dimensions are 29. 75" Width X 7. 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 wear