30"w X 6"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - [Outer Dimensions 31.75"w x 7.75"h] Aluminum Bar + Product Details Perfect Fit

+ Product Details Perfect Fit & Easy Sizing - Designed for a 18" x 16" OR 16" X 18" duct opening (measured at the opening)

+ Product Details Size – 36"w X 34"h is the size for the duct opening measurement only

+ Product Details Size - 10"w X 36"h is the size for the duct opening measurement only

+ Product Details Size - 30"w X 22"h is the size for the duct opening measurement only

+ Product Details Size - 26"w X 14"h is the size for the duct opening measurement only

30"w X 6"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - [Outer Dimensions 31.75"w x 7.75"h] Aluminum Bar + Product Details Perfect Fit+ Product Details Size 30"w X 6"h X 2"d (for duct opening measurement only); actual front end outer dimensions are 31. 75" Width X 7. 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