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] w18h18 + Product Details Perfect Fit

+ Product Details Perfect Fit & Easy Sizing - Designed for a 24" x 12" OR 12" x 24" duct opening (measured at the opening)

Great emphasis has been invested in the design of this product to prevent it from kinking in sharp bends & turns and to hold steady and at full diameter in all applications

875" height

Actual Filter Size – 23 3/4"w x 21 3/4" x 1"

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] w18h18 + Product Details Perfect Fit+ 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