16" x 6" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Compatible with Duct 10" + Product Details Size -

+ Product Details Size - 22"w X 36"h is the size for the duct opening measurement only

actual front end outer dimensions are approximately 20 5/8" width X 28 5/8" height

+ Product Details Size - 24"w X 18"h X 2"d (for duct opening measurement only)

+ Product Details Perfect Fit & Easy Sizing - Designed for a 20" x 12" OR 12" x 20" duct opening (measured at the opening)

16" x 6" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Compatible with Duct 10" + Product Details Size -+ Product Details Perfect Fit & Easy Sizing Designed for a 16" x 6" OR 6" X 16" duct opening (measured at the opening), with actual outer dimensions of 18. 5" W x 8. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 15. 75" x 5. 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 Made