18"w X 36"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - [Outer Dimensions 19.75"w x 37.75"h] w16h16 + Product Details Size – Compatible With Duct 7in Applications This sheet metal DDAG-A-1212

+ Product Details Size – 34"w X 20"h is the size for the duct opening measurement only

+ Product Details Size - 14"w X 34"h X 2"d (for duct opening measurement only)

The installation process is a breeze

+ Product Details Size - 8"w X 36"h is the size for the duct opening measurement only

+ Product Details Perfect Fit & Easy Sizing - Designed for a 12" x 8" or 8" x 12" duct opening (measured at the opening)

18"w X 36"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace Weather Resistant Air Grille with Screen Mesh [Outer Dimensions 19.75"w x 37.75"h] w16h16 + Product Details Size – Compatible With Duct 7in Applications This sheet metal DDAG A 1212 + Product Details Size – 34"w X 20"h is the size for the duct opening measurement only + Product Details Size 14"w X 34"h X 2"d (for duct opening measurement only)