30" x 18" Cube Core Eggcrate Return Air Filter Grille for 1" Filter flat stamped steel + Product Details Size -

+ Product Details Size - 26"w X 16"h is the size for the duct opening measurement only

+ Product Details Size – 14"w X 22"h is the size for the duct opening measurement only

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engineered for seamless 360-degree airflow in T-bar ceilings

Actual Filter Size – 29 3/4"w x 29 3/4" x 1"

30" x 18" Cube Core Eggcrate Return Air Filter Grille for 1" Filter flat stamped steel + Product Details Size -+ Product Details Perfect Fit & Easy Sizing Designed for a 30" x 18" OR 18" x 30" duct opening (measured at the opening), with actual outer dimensions of 32. 5" W x 20. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 29. 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