30"w X 22"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - [Outer Dimensions 31.75"w x 23.75"h] w10h10 Actual Filter Size – 25 10in diameter 75 Plenum Box Depth 1267FLR90

Actual Filter Size – 25 3/4"w x 5 3/4" x 1"

+ Product Details Size - 26"w X 20"h is the size for the duct opening measurement only

+ Product Details Perfect Fit & Easy Sizing - Designed for a 10" x 30" or 30" x 10" duct opening (measured at the opening)

This Will Create A Cycle Of In And Out Air FLow

+ Product Details Size – 34"w X 34"h is the size for the duct opening measurement only

30"w X 22"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace Weather Resistant Air Grille with Screen Mesh [Outer Dimensions 31.75"w x 23.75"h] w10h10 Actual Filter Size – 25 10in diameter 75 Plenum Box Depth 1267FLR90 Actual Filter Size – 25 3 4"w x 5 3 4" x 1" + Product Details Size 26"w X 20"h is the size for the duct opening measurement only