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

+ Product Details Size – 18"w X 24"h is the size for the duct opening measurement only

+ Product Details Size - 16"w X 32"h is the size for the duct opening measurement only

actual front end outer dimensions are approximately 12 5/8" width X 32 5/8" height -

+ Product Details Perfect Fit & Easy Sizing - Designed for a 26" x 28" OR 28" x 26" duct opening (measured at the opening)

+ Product Details Size - 28"w X 18"h is the size for the duct opening measurement only

22" x 20" Cube Core Eggcrate Return Air Filter Grille for 1" Filter d + Product Details Size –+ Product Details Perfect Fit & Easy Sizing Designed for a 22" x 20" OR 20" x 22" duct opening (measured at the opening), with actual outer dimensions of 24. 5" W x 22. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 21. 75" x 19. 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