36" x 30" Cube Core Eggcrate Return Air Filter Grille for 1" Filter 8" Diameter + Product Details Size –

+ Product Details Size – 34"w X 18"h is the size for the duct opening measurement only

75"H – fits a 24" X 10" duct opening

+ Product Details Size - 30"w X 12"h X 2"d (for duct opening measurement only)

Carefully Shrink Wrapped With Cardboard Backing To Prevent Damage In Shipment

+ Product Details Size - 24"w X 4"h is the size for the duct opening measurement only

36" x 30" Cube Core Eggcrate Return Air Filter Grille for 1" Filter 8" Diameter + 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