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] w36h36 10" Diameter Is The Size

10" Diameter Is The Size For The Duct Opening Measurement Only

6" width X 15

+ Product Details Perfect Fit & Easy Sizing - Designed for a 16" x 36" OR 36" X 16" duct opening (measured at the opening)

+ Product Details Size – 32" x 36" or 36" x 32" is the size for the duct opening measurement only

+ Product Description Introducing the 8" Radial Damper – Your Solution for Controlled Airflow

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] w36h36 10" Diameter Is The Size+ 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