20"w X 18"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - [Outer Dimensions 21.75"w x 19.75"h] 6in diameter our damper helps create a

our damper helps create a well-balanced indoor environment

this guard ensures long-lasting protection and security

Airflow – Easy unrestricted airflow for your HVAC system

+ Product Spec Sheet Corner Baseboard Grille Spec Sheet

20"w X 18"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - [Outer Dimensions 21.75"w x 19.75"h] 6in diameter our damper helps create a+ Product Details Size 20"w X 18"h X 2"d (for duct opening measurement only); actual front end outer dimensions are 21. 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