10"w X 10"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - Black [Outer Dimensions 11.75"w x 11.75"h] Grilles + Product Details Perfect Fit

+ Product Details Perfect Fit & Easy Sizing - Designed for a 18" x 10" OR 10" X 18" duct opening (measured at the opening)

75" Width X 13

For 14" Round Duct Opening - Spiral or Flex

+ Product Details Size - 10"w X 18"h is the size for the duct opening measurement only

actual front end outer dimensions are approximately 32 5/8" width X 12 5/8" height

10"w X 10"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - Black [Outer Dimensions 11.75"w x 11.75"h] Grilles + Product Details Perfect Fit+ Product Details Size 10"w X 10"h X 2"d (for duct opening measurement only); actual front end outer dimensions are 11. 75" Width X 11. 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