18"w X 30"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - [Outer Dimensions 19.75"w x 31.75"h] Fixed Blades Adjustable airflow control - by

Adjustable airflow control - by rotating the middle disk

Actual Filter Size – 9 3/4"w x 21 3/4" x 1"

provide precise damper control and superior air dispersion

order a 20x14 grille

Actual Front End Outer Dimensions Are 14" Diameter

18"w X 30"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - [Outer Dimensions 19.75"w x 31.75"h] Fixed Blades Adjustable airflow control - by+ Product Details Size 18"w X 30"h X 2"d (for duct opening measurement only); actual front end outer dimensions are 19. 75" Width X 31. 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