36"w X 26"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - [Outer Dimensions 37.75"w x 27.75"h] Compatible with Duct 6" + Product Details Size -

+ Product Details Size - 8"w X 28"h is the size for the duct opening measurement only

+ Product Details Size – 14" X 4" is the size for the duct opening (floor/vent hole) measurement only

Actual Filter Size – 35 3/4"w x 31 3/4" x 1"

+ Product Details Size – 36"w X 14"h is the size for the duct opening measurement only

+ Product Details Perfect Fit & Easy Sizing - Designed for a 36" x 12" OR 12" x 36" duct opening (measured at the opening)

36"w X 26"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - [Outer Dimensions 37.75"w x 27.75"h] Compatible with Duct 6" + Product Details Size -+ Product Details Size 36"w X 26"h X 2"d (for duct opening measurement only); actual front end outer dimensions are 37. 75" Width X 27. 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