10"w X 14"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - [Outer Dimensions 11.75"w x 15.75"h] w18h18 Design – Multi-shutter damper with

Design – Multi-shutter damper with handle lever for easy opening and closing - screws included

+ Product Details Size - 18"w X 28"h is the size for the duct opening measurement only

Actual Filter Size – 31 3/4"w x 33 3/4" x 1"

+ Product Details Size - 20"w X 10"h is the size for the duct opening measurement only

+ Product Details Perfect Fit & Easy Sizing - Designed for a 10" x 8" or 8" x 10" duct opening (measured at the opening)

10"w X 14"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - [Outer Dimensions 11.75"w x 15.75"h] w18h18 Design – Multi-shutter damper with+ Product Details Size 10"w X 14"h X 2"d (for duct opening measurement only); actual front end outer dimensions are 11. 75" Width X 15. 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