14"w X 6"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - [Outer Dimensions 15.75"w x 7.75"h] 14" Diameter By means of the smooth

By means of the smooth surface

+ Product Details Size - 18"w X 28"h is the size for the duct opening measurement only

and utility rooms

16" Circular Round Aluminum HVAC Supply Grille Air Diffuser - With Butterfly Damper - Vent Duct Cover

Actual Filter Size – 19 3/4"w x 23 3/4" x 1"

14"w X 6"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - [Outer Dimensions 15.75"w x 7.75"h] 14" Diameter By means of the smooth+ Product Details Size 14"w X 6"h X 2"d (for duct opening measurement only); actual front end outer dimensions are 15. 75" Width X 7. 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 wear