6"w X 20"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - [Outer Dimensions 7.75"w x 21.75"h] Insulated Line + Product Details Size –

+ Product Details Size – 20" x 34" or 34" x 20" is the size for the duct opening measurement only

Actual Filter Size – 27 3/4"w x 9 3/4" x 1"

+ Product Details Size - 32"w X 4"h is the size for the duct opening measurement only

For 14" Round Duct Opening - Spiral or Flex

actual front end outer dimensions are approximately 14 5/8" width X 32 5/8" height -

6"w X 20"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - [Outer Dimensions 7.75"w x 21.75"h] Insulated Line + Product Details Size –+ Product Details Size 6"w X 20"h X 2"d (for duct opening measurement only); actual front end outer dimensions are 7. 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 wear