20"w X 12"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - [Outer Dimensions 21.75"w x 13.75"h] w18h18 Ideal for Walls & Ceilings:

Ideal for Walls & Ceilings: Designed for seamless installation in standard 10” x 8” duct openings

85" width X 9

The total outer size of this grille is the listed size plus 2

+ Product Details Size - 30"w X 24"h X 2"d (for duct opening measurement only)

Solid Base for Stability – Built with a solid base for reliable mounting and stability

20"w X 12"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - [Outer Dimensions 21.75"w x 13.75"h] w18h18 Ideal for Walls & Ceilings:+ Product Details Size 20"w X 12"h X 2"d (for duct opening measurement only); actual front end outer dimensions are 21. 75" Width X 13. 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