36"w X 18"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - [Outer Dimensions 37.75"w x 19.75"h] 18" Round Duct Pipe + Product Details Size -

+ Product Details Size - 22"w X 20"h is the size for the duct opening measurement only

The crank handle lever makes it easy to adjust to every weather situation

actual front end outer dimensions are approximately 10 5/8" width X 16 5/8" height

+ Product Details Size - 16"w X 24"h is the size for the duct opening measurement only

Actual Filter Size – 29 3/4"w x 25 3/4" x 1"

36"w X 18"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - [Outer Dimensions 37.75"w x 19.75"h] 18" Round Duct Pipe + Product Details Size -+ Product Details Size 36"w X 18"h X 2"d (for duct opening measurement only); actual front end outer dimensions are 37. 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