26" x 18" Cube Core Eggcrate Return Air Filter Grille for 1" Filter 12in diameter 875" width X 7

875" width X 7

Actual Filter Size – 11 3/4"w x 25 3/4" x 1"

6" width X 13

actual front end outer dimensions are approximately 35

listed size +2" diameter

26" x 18" Cube Core Eggcrate Return Air Filter Grille for 1" Filter 12in diameter 875" width X 7+ Product Details Perfect Fit & Easy Sizing Designed for a 26" x 18" OR 18" x 26" duct opening (measured at the opening), with actual outer dimensions of 28. 5" W x 20. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 25. 75" x 17. 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