14" x 18" or 18" x 14" Cube Core Eggcrate Return Air Filter Grille for 1" Filter w32h32 75"H – fits a 18"

75"H – fits a 18" X 6" duct opening

10"w X 3"h Is The Size For The Duct Opening Measurement Only

+ Product Details Size – 20"w X 36"h is the size for the duct opening measurement only

+ Product Details Size – 16" x 18" or 18" x 16" is the size for the duct opening measurement only

875" width X 14" height

14" x 18" or 18" x 14" Cube Core Eggcrate Return Air Filter Grille for 1" Filter w32h32 75"H – fits a 18"+ Product Details Perfect Fit & Easy Sizing Designed for a 14" x 18" OR 18" X 14" duct opening (measured at the opening), with actual outer dimensions of 16. 5" W x 20. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 13. 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