20"w X 10"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - [Outer Dimensions 21.75"w x 11.75"h] w28h28 + Product Details Size -

+ Product Details Size - 16"w X 16"h is the size for the duct opening measurement only

For 8" duct opening

actual front end outer dimensions are approximately 36 5/8" width X 34 5/8" height

+ Product Description Upgrade your HVAC system with our heavy-duty

Ideal for Walls & Ceilings: Designed for seamless installation in standard 24" X 10" duct openings

20"w X 10"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - [Outer Dimensions 21.75"w x 11.75"h] w28h28 + Product Details Size -+ Product Details Size 20"w X 10"h X 2"d (for duct opening measurement only); actual front end outer dimensions are 21. 75" Width X 11. 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