28" x 34" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Compatible with Duct 6" Width vs Height:

Width vs Height:

Powder-coat finish

+ Product Details Size - 40"w X 20"h is the size for the duct opening measurement only

+ Product Details Size - 22"w X 10"h is the size for the duct opening measurement only

+ Product Details Perfect Fit & Easy Sizing - Designed for a 20" x 6" OR 6" x 20" duct opening (measured at the opening)

28" x 34" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Compatible with Duct 6" Width vs Height:+ Product Details Perfect Fit & Easy Sizing Designed for a 28" x 34" OR 34" x 28" duct opening (measured at the opening), with actual outer dimensions of 30. 5" W x 36. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 27. 75" x 33. 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