6" x 26" or 26" x 6" Cube Core Eggcrate Return Air Filter Grille for 1" Filter - Aluminum - White [Outer Dimensions: 8.5" X 28.5"] 8in diameter actual front end outer dimensions

actual front end outer dimensions are 19" Width X 13" Height

The 1/2" white insulation

+ Product Details Perfect Fit & Easy Sizing - Designed for a 10" x 10" duct opening (measured at the opening)

Easy Installation – Complete set of sponge gasket and mounting frame included

+ Product Details Size - 30"w X 12"h X 2"d (for duct opening measurement only)

6" x 26" or 26" x 6" Cube Core Eggcrate Return Air Filter Grille for 1" Filter - Aluminum - White [Outer Dimensions: 8.5" X 28.5"] 8in diameter actual front end outer dimensions+ Product Details Perfect Fit & Easy Sizing Designed for a 6" x 26" or 26" x 6" duct opening (measured at the opening), with actual outer dimensions of 8. 5" W x 28. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 5. 75" x 25. 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