10"w X 8"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - [Outer Dimensions 11.75"w x 9.75"h] Compatible With Duct 12in Ideal for Walls & Ceilings:

Ideal for Walls & Ceilings: Designed for seamless installation in standard 14" X 10" duct openings

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

10"w X 3"h Is The Size For The Duct Opening Measurement Only

+ Product Details Perfect Fit & Easy Sizing - Designed for a 20" x 32" OR 32" x 20" duct opening (measured at the opening)

actual front end outer dimensions are approximately 36 5/8" width X 38 5/8" height

10"w X 8"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - [Outer Dimensions 11.75"w x 9.75"h] Compatible With Duct 12in Ideal for Walls & Ceilings:+ Product Details Size 10"w X 8"h X 2"d (for duct opening measurement only); actual front end outer dimensions are 11. 75" Width X 9. 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 wear