6" x 28" or 28" x 6" Cube Core Eggcrate Return Air Filter Grille for 1" Filter - Aluminum - White [Outer Dimensions: 8.5" X 30.5"] Color_Red Oak Wood + Product Details Size -

+ Product Details Size - 18"w X 8"h is the size for the duct opening measurement only

designed to optimize your air distribution

24"w X 6"h Is The Size For The Duct Opening Measurement Only

guaranteeing efficient ventilation throughout your space

no questions asked

6" x 28" or 28" x 6" Cube Core Eggcrate Return Air Filter Grille for 1" Filter - Aluminum - White [Outer Dimensions: 8.5" X 30.5"] Color_Red Oak Wood + Product Details Size -+ Product Details Perfect Fit & Easy Sizing Designed for a 6" x 28" or 28" x 6" duct opening (measured at the opening), with actual outer dimensions of 8. 5" W x 30. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 5. 75" x 27. 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 Made