20" x 16" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Material_Aluminum + Product Details Size –

+ Product Details Size – 26"w X 6"h is the size for the duct opening measurement only

+ Product Details Perfect Fit & Easy Sizing - Designed for a 8" x 18" or 18" x 8" duct opening (measured at the opening)

+ Product Details Size - 20"w X 6"h is the size for the duct opening measurement only

width: 100%

excluding the old vent cover

20" x 16" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Material_Aluminum + Product Details Size –+ Product Details Perfect Fit & Easy Sizing Designed for a 20" x 16" OR 16" x 20" duct opening (measured at the opening), with actual outer dimensions of 22. 5" W x 18. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 19. 75" x 15. 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