36"w X 24"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - [Outer Dimensions 37.75"w x 25.75"h] w8h8 Actual Filter Size – 15

Actual Filter Size – 15 3/4"w x 19 3/4" x 1"

Optional Butterfly Damper Available At Asin: B007CNEL1W

actual front end outer dimensions are approximately 18 5/8" width X 16 5/8" height

+ Product Details Universal Fit - Accommodates almost any thermostat with dimensions of 8-1/4" H x 5-3/8" W x 3-1/2" D

+ Product Details Size – 14" X 4" is the size for the duct opening (floor/vent hole) measurement only

36"w X 24"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - [Outer Dimensions 37.75"w x 25.75"h] w8h8 Actual Filter Size – 15+ Product Details Size 36"w X 24"h X 2"d (for duct opening measurement only); actual front end outer dimensions are 37. 75" Width X 25. 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