18" x 28" or 28" x 18" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Outdoor Vent Covers allowing unrestricted airflow for optimal

allowing unrestricted airflow for optimal HVAC performance

please note that the total outer dimensions of the grille measure 7" in diameter

ensuring consistent and efficient air distribution throughout your space

this register is built to perform and look great for years to come

18" x 28" or 28" x 18" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Outdoor Vent Covers allowing unrestricted airflow for optimal+ Product Details Perfect Fit & Easy Sizing Designed for a 18" x 28" OR 28" x 18" duct opening (measured at the opening), with actual outer dimensions of 20. 5" W x 30. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 17. 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