30" x 24" Cube Core Eggcrate Return Air Filter Grille for 1" Filter 12" Diameter + Product Details Size -

+ Product Details Size - 6"w X 32"h is the size for the duct opening measurement only

making it perfect for both residential and commercial installations

+ Product Details Size – 28"w X 20"h is the size for the duct opening measurement only

actual front end outer dimensions are approximately 36 5/8" width X 18 5/8" height

+ Product Details Size - 20"w X 4"h is the size for the duct opening measurement only

30" x 24" Cube Core Eggcrate Return Air Filter Grille for 1" Filter 12" Diameter + Product Details Size -+ Product Details Perfect Fit & Easy Sizing Designed for a 30" x 24" OR 24" x 30" duct opening (measured at the opening), with actual outer dimensions of 32. 5" W x 26. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 29. 75" x 23. 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