16"w X 6"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - [Outer Dimensions 17.75"w x 7.75"h] Aluminum Bar + Product Details Size -

+ Product Details Size - 20"w X 28"h X 2"d (for duct opening measurement only)

875" width X 18" height

+ Product Details Size – 34"w X 30"h is the size for the duct opening measurement only

875" width X 25

+ Product Details Size - 24"w X 8"h is the size for the duct opening measurement only

16"w X 6"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - [Outer Dimensions 17.75"w x 7.75"h] Aluminum Bar + Product Details Size -+ Product Details Size 16"w X 6"h X 2"d (for duct opening measurement only); actual front end outer dimensions are 17. 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