18" x 24" Cube Core Eggcrate Return Air Filter Grille for 1" Filter White 4" X 10" Is The

4" X 10" Is The Size For The Duct Opening (floor/vent hole) Measurement Only

+ Product Details Size - 30"w X 2"h is the size for the duct opening measurement only

+ Product Details Size - 16"w X 25"h is the size for the duct opening measurement only

minimizing waste

actual front end outer dimensions are approximately 25

18" x 24" Cube Core Eggcrate Return Air Filter Grille for 1" Filter White 4" X 10" Is The+ Product Details Perfect Fit & Easy Sizing Designed for a 18" x 24" OR 24" x 18" duct opening (measured at the opening), with actual outer dimensions of 20. 5" W x 26. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 17. 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