36" x 24" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Grilles + Product Details Size –

+ Product Details Size – 18"w X 12"h is the size for the duct opening measurement only

This grille has a high standard of design

Made from high-grade stamped steel

Filter Size - 17

36" x 24" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Grilles + Product Details Size –+ Product Details Perfect Fit & Easy Sizing Designed for a 36" x 24" OR 24" x 36" duct opening (measured at the opening), with actual outer dimensions of 38. 5" W x 26. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 35. 75" x 23. 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