HVAC Premium 18"w X 18"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - [Outer Dimensions 19.75"w x 19.75"h] Round Damper Ring + Product Details Size -

+ Product Details Size - 24"w X 18"h is the size for the duct opening measurement only

3/8" - 4223 PSI

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

Whether you're restoring an old Victorian or craftsman style home

Tough reinforced metallized polyester jacket - tear and puncture resistant

HVAC Premium 18"w X 18"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - [Outer Dimensions 19.75"w x 19.75"h] Round Damper Ring + Product Details Size -+ Product Details Size 18"w X 18"h X 2"d (for duct opening measurement only); actual front end outer dimensions are 19. 75" Width X 19. 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