12"w X 12"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - Black [Outer Dimensions 13.75"w x 13.75"h] w36h36 actual front end outer dimensions

actual front end outer dimensions are approximately 38 5/8" width X 22 5/8" height -

+ Product Details Size – 20"w X 4"h is the size for the duct opening measurement only

listed size +1

+ Product Details Perfect Fit & Easy Sizing - Designed for a 30" x 34" OR 34" x 30" duct opening (measured at the opening)

+ Product Details Perfect Fit & Easy Sizing - Designed for a 14" x 12" or 12" x 14" duct opening (measured at the opening)

12"w X 12"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - Black [Outer Dimensions 13.75"w x 13.75"h] w36h36 actual front end outer dimensions+ Product Details Size 12"w X 12"h X 2"d (for duct opening measurement only); actual front end outer dimensions are 13. 75" Width X 13. 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