28"w X 30"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - [Outer Dimensions 29.75"w x 31.75"h] Grilles Design – These are specially 4 X 12 Is CRFG2028 Width_14in

Design – These are specially sized to fit into all drop ceilings

actual front end outer dimensions are 7

+ Product Details Size - 25"w X 14"h is the size for the duct opening measurement only

+ Product Details Perfect Fit & Easy Sizing - Designed for a 26" x 12" OR 12" x 26" duct opening (measured at the opening)

+ Product Details Size - 24"w X 18"h is the size for the duct opening measurement only

28"w X 30"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace Weather Resistant Air Grille with Screen Mesh [Outer Dimensions 29.75"w x 31.75"h] Grilles Design – These are specially 4 X 12 Is CRFG2028 Width_14in Design – These are specially sized to fit into all drop ceilings actual front end outer dimensions are 7