16"w X 16"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - White [Outer Dimensions 17.75"w x 17.75"h] 10in diameter + Product Details Size –

+ Product Details Size – 20" x 20" is the size for the duct opening measurement only

+ Product Details Size - 16"w X 24"h X 2"d (for duct opening measurement only)

+ Product Details Size – 10"w X 12"h is the size for the duct opening measurement only

with actual outer dimensions of 30

16"w X 16"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - White [Outer Dimensions 17.75"w x 17.75"h] 10in diameter + Product Details Size –+ Product Details Size 16"w X 16"h X 2"d (for duct opening measurement only); actual front end outer dimensions are 17. 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