20"w X 26"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - [Outer Dimensions 21.75"w x 27.75"h] 12in diameter actual front end outer dimensions

actual front end outer dimensions are approximately 30 5/8" width X 10 5/8" height

+ Product Details Perfect Fit & Easy Sizing - Designed for a 34" x 28" Or 28" x 34" duct opening (measured at the opening)

+ Product Details Size - 24"w X 22"h is the size for the duct opening measurement only

this flex duct decreases the pressure loss and provides a more hygienic environment

+ Product Details Perfect Fit & Easy Sizing - Designed for a 14" x 18" OR 18" X 14" duct opening (measured at the opening)

20"w X 26"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - [Outer Dimensions 21.75"w x 27.75"h] 12in diameter actual front end outer dimensions+ Product Details Size 20"w X 26"h X 2"d (for duct opening measurement only); actual front end outer dimensions are 21. 75" Width X 27. 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