14" x 24" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Color_Aluminum + Product Details Size –

+ Product Details Size – 16"w X 20"h is the size for the duct opening measurement only

actual front end outer dimensions are approximately 16 5/8" width X 10 5/8" height

+ Product Details Size - 20"w X 18"h is the size for the duct opening measurement only

actual front end outer dimensions are approximately 21

14" x 24" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Color_Aluminum + Product Details Size –+ Product Details Perfect Fit & Easy Sizing Designed for a 14" x 24" OR 24" X 14" duct opening (measured at the opening), with actual outer dimensions of 16. 5" W x 26. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 13. 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