16" x 28" or 28" x 16" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Fixed Blades + Product Details Size –

+ Product Details Size – 8"w X 24"h is the size for the duct opening measurement only

Made of high quality aluminum that will never rust

Please check the measuring guide to ensure a proper fit

+ Product Details Perfect Fit & Easy Sizing - Designed for a 20" x 28" OR 28" x 20" duct opening (measured at the opening)

16" x 28" or 28" x 16" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Fixed Blades + Product Details Size –+ Product Details Perfect Fit & Easy Sizing Designed for a 16" x 28" OR 28" X 16" duct opening (measured at the opening), with actual outer dimensions of 18. 5" W x 30. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 15. 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