8"w X 16"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - Brown [Outer Dimensions 9.75"w x 17.75"h] Compatible With Duct 8in + Product Details Size -

+ Product Details Size - 20"w X 6"h is the size for the duct opening measurement only

actual front end outer dimensions are approximately 30 5/8" width X 16 5/8" height -

+ Product Details Perfect Fit & Easy Sizing - Designed for a 8" x 34" or 34" x 8" duct opening (measured at the opening)

Superior Airflow Control: Built-in damper lets you control how much air enters your room

background-color: #000

8"w X 16"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - Brown [Outer Dimensions 9.75"w x 17.75"h] Compatible With Duct 8in + Product Details Size -+ Product Details Size 8"w X 16"h X 2"d (for duct opening measurement only); actual front end outer dimensions are 9. 75" Width X 17. 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 wear