16"w X 18"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - [Outer Dimensions 17.75"w x 19.75"h] 14" Round Duct Pipe 875" width X 13

875" width X 13

with actual front end outer dimensions of 6"

75"H – fits a 20" X 18" duct opening

width: 100%

+ Product Details Perfect Fit & Easy Sizing - Designed for a 16" x 30" OR 30" X 16" duct opening (measured at the opening)

16"w X 18"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - [Outer Dimensions 17.75"w x 19.75"h] 14" Round Duct Pipe 875" width X 13+ Product Details Size 16"w X 18"h X 2"d (for duct opening measurement only); actual front end outer dimensions are 17. 75" Width X 19. 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