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"] RV Mobile Home + Product Details Perfect Fit

+ Product Details Perfect Fit & Easy Sizing - Designed for a 18" x 26" OR 26" x 18" duct opening (measured at the opening)

Ideal for Walls & Ceilings: Designed for seamless installation in standard 10" X 10" duct openings

+ Product Details Perfect Fit & Easy Sizing - Designed for a 12" x 16" or 16" x 12" duct opening (measured at the opening)

and waste gases transmission lines

These are specially sized to fit into all drop ceilings

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"] RV Mobile Home + Product Details Perfect Fit+ 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