20"w X 24"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - [Outer Dimensions 21.75"w x 25.75"h] ceiling + Product Details Size -

+ Product Details Size - 16"w X 26"h is the size for the duct opening measurement only

Actual Filter Size – 29 3/4"w x 23 3/4" x 1"

+ Product Details Size - 30"w X 12"h X 2"d (for duct opening measurement only)

Universal Fit – Measures 3-7/8" wide x 3-1/2" high x 3" deep

+ Product Details Size – 25"w X 12"h is the size for the duct opening measurement only

20"w X 24"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - [Outer Dimensions 21.75"w x 25.75"h] ceiling + Product Details Size -+ Product Details Size 20"w X 24"h X 2"d (for duct opening measurement only); actual front end outer dimensions are 21. 75" Width X 25. 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