6"w X 24"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - [Outer Dimensions 7.75"w x 25.75"h] 1-Way + Product Details Size -

+ Product Details Size - 10"w X 16"h is the size for the duct opening measurement only

border-radius: 50%

Slots are angled to diversify the airflow in 2 way direction

+ Product Details Perfect Fit & Easy Sizing - Designed for a 26" x 24" OR 24" x 26" duct opening (measured at the opening)

+ Product Details Size – 18"w X 30"h is the size for the duct opening measurement only

6"w X 24"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - [Outer Dimensions 7.75"w x 25.75"h] 1-Way + Product Details Size -+ Product Details Size 6"w X 24"h X 2"d (for duct opening measurement only); actual front end outer dimensions are 7. 75" Width X 25. 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