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

+ Product Details Size – 8" x 26" or 26" x 8" is the size for the duct opening measurement only

Actual Filter Size – 9 3/4"w x 17 3/4" x 1"

+ Product Details Size - 16"w X 14"h X 2"d (for duct opening measurement only)

actual front end outer dimensions are 16" width X 8" height

actual front end outer dimensions are approximately 22 5/8" width X 52 5/8" height

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