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] Copper Coil-Insulated Line Set + Product Details Size -

+ Product Details Size - 30"w X 12"h is the size for the duct opening measurement only

+ Product Details Size – 14" x 30" or 30" x 14" is the size for the duct opening measurement only

+ Product Details Perfect Fit & Easy Sizing - Designed for a 20" x 25" OR 25" x 20" duct opening (measured at the opening)

+ Product Details Size - 25"w X 30"h is the size for the duct opening measurement only

actual front end outer dimensions are approximately 52 5/8" width X 22 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] Copper Coil-Insulated Line Set + Product Details Size -+ 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