12" x 16" or 16" x 12" Cube Core Eggcrate Return Air Filter Grille for 1" Filter - Aluminum - White [Outer Dimensions: 14.5" X 18.5"] Aluminum Adjustable Curved Blade + Product Details Perfect Fit

+ Product Details Perfect Fit & Easy Sizing - Designed for a 12" x 36" or 36" x 12" duct opening (measured at the opening)

Actual Filter Size – 23 3/4"w x 9 3/4" x 1"

Upgrade your HVAC system with our cutting-edge 360-degree airflow grill

+ Product Details Size – 20" x 26 or 26" x 20" is the size for the duct opening measurement only

12" x 16" or 16" x 12" Cube Core Eggcrate Return Air Filter Grille for 1" Filter - Aluminum - White [Outer Dimensions: 14.5" X 18.5"] Aluminum Adjustable Curved Blade + Product Details Perfect Fit+ Product Details Perfect Fit & Easy Sizing Designed for a 12" x 16" or 16" x 12" duct opening (measured at the opening), with actual outer dimensions of 14. 5" W x 18. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 11. 75" x 15. 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