8"w X 8"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - White [Outer Dimensions 9.75"w x 9.75"h] 18in diameter + Product Details Size -

+ Product Details Size - 34"w X 12"h is the size for the duct opening measurement only

+ Product Details Size - 36"w X 32"h is the size for the duct opening measurement only

and sound level range of NC 25 to 35

actual front end outer dimensions are approximately 34 5/8" width X 14 5/8" height

8"w X 8"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - White [Outer Dimensions 9.75"w x 9.75"h] 18in diameter + Product Details Size -+ Product Details Size 8"w X 8"h X 2"d (for duct opening measurement only); actual front end outer dimensions are 9. 75" Width X 9. 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