18"w X 22"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - [Outer Dimensions 19.75"w x 23.75"h] 12in diameter Actual Filter Size – 24

Actual Filter Size – 24 3/4"w x 9 3/4" x 1"

Scratch-Resistant

Actual Filter Size – 11 3/4"w x 25 3/4" x 1"

+ Product Details Size - 4"w X 24"h is the size for the duct opening measurement only

+ Product Details Size – 24" x 24" with 8" collar T-Bar drop ceiling perforated return grill - metal back casing

18"w X 22"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - [Outer Dimensions 19.75"w x 23.75"h] 12in diameter Actual Filter Size – 24+ Product Details Size 18"w X 22"h X 2"d (for duct opening measurement only); actual front end outer dimensions are 19. 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