16"w X 34"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - [Outer Dimensions 17.75"w x 35.75"h] 10" Diameter + Product Details Size –

+ Product Details Size – 18" x 34" or 34" x 18" is the size for the duct opening measurement only

Actual Filter Size – 17 3/4"w x 27 3/4" x 1"

One model suits both T-Bar and Drywall installations

+ Product Details Size - The listed 12" diameter refers specifically to the size of the duct opening

+ Product Details Perfect Fit & Easy Sizing - Designed for a 32" x 10" OR 10" x 32" duct opening (measured at the opening)

16"w X 34"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - [Outer Dimensions 17.75"w x 35.75"h] 10" Diameter + Product Details Size –+ Product Details Size 16"w X 34"h X 2"d (for duct opening measurement only); actual front end outer dimensions are 17. 75" Width X 35. 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