30"w X 16"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - [Outer Dimensions 31.75"w x 17.75"h] 6in diameter + Product Details Size -

+ Product Details Size - 28"w X 24"h X 2"d (for duct opening measurement only)

Width vs Height:

+ Product Details Size – 12" x 16" or 16" x 12" is the size for the duct opening measurement only

+ Product Details Perfect Fit & Easy Sizing - Designed for a 16" x 30" OR 30" X 16" duct opening (measured at the opening)

unrestricted airflow with a precise 50° angled design

30"w X 16"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - [Outer Dimensions 31.75"w x 17.75"h] 6in diameter + Product Details Size -+ Product Details Size 30"w X 16"h X 2"d (for duct opening measurement only); actual front end outer dimensions are 31. 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