18"w X 32"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - [Outer Dimensions 19.75"w x 33.75"h] w36h36 + Product Details Size –

+ Product Details Size – 22"w X 8"h is the size for the duct opening measurement only

+ Product Details Perfect Fit & Easy Sizing - Designed for a 16" x 25" OR 25" X 16" duct opening (measured at the opening)

+ Product Details Perfect Fit & Easy Sizing - Designed for a 20" x 8" OR 8" x 20" duct opening (measured at the opening)

Its smooth

18"w X 32"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - [Outer Dimensions 19.75"w x 33.75"h] w36h36 + Product Details Size –+ Product Details Size 18"w X 32"h X 2"d (for duct opening measurement only); actual front end outer dimensions are 19. 75" Width X 33. 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