24"w X 36"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - [Outer Dimensions 25.75"w x 37.75"h] White Actual Filter Size – 21

Actual Filter Size – 21 3/4"w x 15 3/4" x 1"

Actual Filter Size – 17 3/4"w x 27 3/4" x 1"

actual front end outer dimensions are approximately 16 5/8" width X 27 5/8" height

and with a built-in back 1/2" mesh they also protect you from annoying rodents like mice

24"w X 36"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - [Outer Dimensions 25.75"w x 37.75"h] White Actual Filter Size – 21+ Product Details Size 24"w X 36"h X 2"d (for duct opening measurement only); actual front end outer dimensions are 25. 75" Width X 37. 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