36" x 30" Cube Core Eggcrate Return Air Filter Grille for 1" Filter ceiling + Product Details Size –

+ Product Details Size – 20" x 22" or 22" x 20" is the size for the duct opening measurement only

+ Product Details Perfect Fit & Easy Sizing - Designed for a 24" x 6" OR 6" x 24" duct opening (measured at the opening)

Actual Front End Outer Dimensions Are 14" Width X 10" Height - SEE IN DESCRIPTION HOW TO MEASURE A GRILLE

+ Product Details Perfect Fit & Easy Sizing - Designed for a 34" x 24" Or 24" x 34" duct opening (measured at the opening)

+ Product Details Perfect Fit & Easy Sizing - Designed for a 14" x 34" OR 34" X 14" duct opening (measured at the opening)

36" x 30" Cube Core Eggcrate Return Air Filter Grille for 1" Filter ceiling + Product Details Size –+ Product Details Perfect Fit & Easy Sizing Designed for a 36" x 30" OR 30" x 36" duct opening (measured at the opening), with actual outer dimensions of 38. 5" W x 32. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 35. 75" x 29. 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