36"w X 36"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - [Outer Dimensions 37.75"w x 37.75"h] Color_R-4.2 Yellow with actual outer dimensions of

with actual outer dimensions of 18

+ Product Details Size - 18"w X 24"h is the size for the duct opening measurement only

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

Actual Filter Size – 7 3/4"w x 15 3/4" x 1"

+ Product Details Size - 20"w X 14"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 - [Outer Dimensions 37.75"w x 37.75"h] Color_R-4.2 Yellow with actual outer dimensions of+ 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