12" x 20" Cube Core Eggcrate Return Air Filter Grille for 1" Filter w16h16 + Product Details Size -

+ Product Details Size - 24"w X 10"h is the size for the duct opening measurement only

+ Product Details Size - 28"w X 8"h is the size for the duct opening measurement only

and its seamless drop-in installation process ensures effortless setup

+ Product Details Size - 34"w X 24"h is the size for the duct opening measurement only

12" x 20" Cube Core Eggcrate Return Air Filter Grille for 1" Filter w16h16 + 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