26"w X 6"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - [Outer Dimensions 27.75"w x 7.75"h] white ISO Supply Diffusers perform efficiently

ISO Supply Diffusers perform efficiently with air loadings of 6 to 30 air changes per hour (based on 10 ft

4" X 10" Brass Victorian Floor Register Grille - Modern Contempo Decorative Grate - HVAC Vent Duct Cover - Brass Plated

actual front end outer dimensions are approximately 18 5/8" width X 24 5/8" height

+ Product Details Size - 16"w X 34"h X 2"d (for duct opening measurement only)

+ Product Details Size – 22"w X 25"h is the size for the duct opening measurement only

26"w X 6"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - [Outer Dimensions 27.75"w x 7.75"h] white ISO Supply Diffusers perform efficiently+ Product Details Size 26"w X 6"h X 2"d (for duct opening measurement only); actual front end outer dimensions are 27. 75" Width X 7. 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