36"w X 20"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - [Outer Dimensions 37.75"w x 21.75"h] Fixed Blades + Product Details Size -

+ Product Details Size - 8"w X 8"h X 2"d (for duct opening measurement only)

Design – Unrestricted airflow for your HVAC system - adjustable one-way louver with full horizontal airflow directional control - single deflection supply grill with 96% airflow - noise free components - no vibrating louvers etc

+ How To Measure A Round Vent Overall Size:

+ Product Details Size – 10"w X 34"h is the size for the duct opening measurement only

+ Product Details Size – 12"w X 4"h is the size for the duct opening measurement only

36"w X 20"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - [Outer Dimensions 37.75"w x 21.75"h] Fixed Blades + Product Details Size -+ Product Details Size 36"w X 20"h X 2"d (for duct opening measurement only); actual front end outer dimensions are 37. 75" Width X 21. 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