36"w X 36"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - Black [Outer Dimensions 37.75"w x 37.75"h] 14" Diameter Design – Rigid gauge built

Design – Rigid gauge built for durability and long life in mind

+ Product Details Size – 18"w X 25"h is the size for the duct opening measurement only

+ Product Details Perfect Fit & Easy Sizing - Designed for a 6" x 22" or 22" x 6" duct opening (measured at the opening)

+ Product Details Size – 12"w X 8"h is the size for the duct opening measurement only

36"w X 36"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - Black [Outer Dimensions 37.75"w x 37.75"h] 14" Diameter Design – Rigid gauge built+ Product Details Size 36"w X 36"h X 2"d (for duct opening measurement only); actual front end outer dimensions are 37. 75" Width X 37. 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