18" x 20" or 20" x 18" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Round Damper Ring resisting rust and wear while

resisting rust and wear while adding a sleek

Say goodbye to pest-related worries as the built-in back 1/2" mesh acts as a barrier against unwanted rodents like mice

Achieve the perfect airflow with adjustable control by rotating the middle disk

+ Product Details Size – 6" x 16" or 16" x 6" is the size for the duct opening measurement only

18" x 20" or 20" x 18" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Round Damper Ring resisting rust and wear while+ Product Details Perfect Fit & Easy Sizing Designed for a 18" x 20" OR 20" x 18" duct opening (measured at the opening), with actual outer dimensions of 20. 5" W x 22. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 17. 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