12" x 20" Cube Core Eggcrate Return Air Filter Grille for 1" Filter w6h6 + Product Details Size -

+ Product Details Size - 30"w X 8"h is the size for the duct opening measurement only

Crafted for durability and rust-resistance

+ Product Details Size - 8"w X 36"h is the size for the duct opening measurement only

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

12" x 20" Cube Core Eggcrate Return Air Filter Grille for 1" Filter w6h6 + Product Details Size -+ Product Details Perfect Fit & Easy Sizing Designed for a 12" x 20" or 20" x 12" duct opening (measured at the opening), with actual outer dimensions of 14. 5" W x 22. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 11. 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