20"w X 20"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - [Outer Dimensions 21.75"w x 21.75"h] w36h36 Measure the size of the

Measure the size of the vent opening

Actual Filter Size – 9 3/4"w x 7 3/4" x 1"

actual front end outer dimensions are approximately 10 5/8" width X 20 5/8" height

How To Measure A Grille

20"w X 20"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - [Outer Dimensions 21.75"w x 21.75"h] w36h36 Measure the size of the+ Product Details Size 20"w X 22"h X 2"d (for duct opening measurement only); actual front end outer dimensions are 21. 75" Width X 23. 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