20"w X 24"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - [Outer Dimensions 21.75"w x 25.75"h] Ceiling actual front end outer dimensions Compatible With Duct 7in Applications This sheet metal DDAG-A-1212

actual front end outer dimensions are approximately 16 5/8" width X 22 5/8" height

+ Product Details Size - 16"w X 12"h is the size for the duct opening measurement only

Ideal for Walls & Ceilings: Designed for seamless installation in standard 20" X 8" duct openings

+ Product Details Size - 22"w X 18"h X 2"d (for duct opening measurement only)

Adjustable airflow control - by rotating the middle disk

20"w X 24"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace Weather Resistant Air Grille with Screen Mesh [Outer Dimensions 21.75"w x 25.75"h] Ceiling actual front end outer dimensions Compatible With Duct 7in Applications This sheet metal DDAG A 1212 actual front end outer dimensions are approximately 16 5 8" width X 22 5 8" height + Product Details Size 16"w X 12"h is the size for the duct opening measurement only