34" x 28" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Filter Grille Measuring 3" in diameter for

Measuring 3" in diameter for the duct opening

Please check the measuring guide to ensure a proper fit

+ Product Details Size – 28"w X 18"h is the size for the duct opening measurement only

Control Your Airflow on drop ceiling grilles

Made of High Quality Aluminum That Will Never Rust

34" x 28" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Filter Grille Measuring 3" in diameter for+ Product Details Perfect Fit & Easy Sizing Designed for a 34" x 28" Or 28" x 34" duct opening (measured at the opening), with actual outer dimensions of 36. 5" W x 30. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 33. 75" x 27. 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