8"w X 6"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - [Outer Dimensions 9.75"w x 7.75"h] 8" Round Duct Pipe + Product Details Size –

+ Product Details Size – 28"w X 30"h is the size for the duct opening measurement only

Actual Filter Size – 7 3/4"w x 19 3/4" x 1"

with no sharp edges

actual front end outer dimensions are approximately 20 5/8" width X 14 5/8" height

Tailored for Your Needs: Specifically suited for 24x24 lay-in diffusers

8"w X 6"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - [Outer Dimensions 9.75"w x 7.75"h] 8" Round Duct Pipe + Product Details Size –+ Product Details Size 8"w X 6"h X 2"d (for duct opening measurement only); actual front end outer dimensions are 9. 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