24" x 30" Cube Core Eggcrate Return Air Filter Grille for 1" Filter 6in diameter Filter Size - 21

Filter Size - 21

+ Product Details Perfect Fit & Easy Sizing - Designed for a 18" x 28" OR 28" x 18" duct opening (measured at the opening)

75" width X 19

height: 22px

+ Product Details Perfect Fit & Easy Sizing - Designed for a 26" x 22" OR 22" x 26" duct opening (measured at the opening)

24" x 30" Cube Core Eggcrate Return Air Filter Grille for 1" Filter 6in diameter Filter Size - 21+ Product Details Perfect Fit & Easy Sizing Designed for a 24" x 30" OR 30" x 24" duct opening (measured at the opening), with actual outer dimensions of 26. 5" W x 32. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 23. 75" x 29. 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