12"w X 12"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - Brown [Outer Dimensions 13.75"w x 13.75"h] Compatible With Duct 10in + Product Details Size -

+ Product Details Size - 28"w X 6"h is the size for the duct opening measurement only

75" Width X 21

this guard is designed to provide maximum protection against tampering while maintaining a clean and professional appearance

+ Product Details Size – 24" x 30" or 30" x 24" is the size for the duct opening measurement only

actual front end outer dimensions are approximately 18 5/8" width X 38 5/8" height

12"w X 12"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - Brown [Outer Dimensions 13.75"w x 13.75"h] Compatible With Duct 10in + Product Details Size -+ Product Details Size 12"w X 12"h X 2"d (for duct opening measurement only); actual front end outer dimensions are 13. 75" Width X 13. 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