26" x 20" Cube Core Eggcrate Return Air Filter Grille for 1" Filter 10" Diameter + Product Details Size -

+ Product Details Size - 30"w X 14"h is the size for the duct opening measurement only

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+ Product Details Size - 32"w X 25"h is the size for the duct opening measurement only

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

26" x 20" Cube Core Eggcrate Return Air Filter Grille for 1" Filter 10" Diameter + Product Details Size -+ Product Details Perfect Fit & Easy Sizing Designed for a 26" x 20" OR 20" x 26" duct opening (measured at the opening), with actual outer dimensions of 28. 5" W x 22. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 25. 75" x 19. 75" x 1" Premium Airflow Efficiency High performance cube core eggcrate design allows 95% airflow efficiency, reducing energy costs and maximizing HVAC system lifespan. Durable, Rust Free Aluminum