20"w X 28"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - [Outer Dimensions 21.75"w x 29.75"h] 1-Way providing a perfect fit for

providing a perfect fit for most standard thermostats

+ Product Details Size - 32"w X 18"h is the size for the duct opening measurement only

Actual Front End Outer Dimensions Are 12" Width X 4" Height - SEE IN DESCRIPTION HOW TO MEASURE A GRILLE

Ideal for Walls & Ceilings: Designed for seamless installation in standard 20" X 10" duct openings

20"w X 28"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - [Outer Dimensions 21.75"w x 29.75"h] 1-Way providing a perfect fit for+ Product Details Size 20"w X 28"h X 2"d (for duct opening measurement only); actual front end outer dimensions are 21. 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