36" x 12" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Compatible with Duct 6" Actual Filter Size – 31

Actual Filter Size – 31 3/4"w x 17 3/4" x 1"

and slashes energy costs

adds an extra layer of protection

+ Product Details Perfect Fit & Easy Sizing - Designed for a 20" x 36" OR 36" x 20" duct opening (measured at the opening)

36" x 12" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Compatible with Duct 6" Actual Filter Size – 31+ Product Details Perfect Fit & Easy Sizing Designed for a 36" x 12" OR 12" x 36" duct opening (measured at the opening), with actual outer dimensions of 38. 5" W x 14. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 35. 75" x 11. 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