30" x 10" Cube Core Eggcrate Return Air Filter Grille for 1" Filter 18" Round Duct Pipe + Product Details Perfect Fit

+ Product Details Perfect Fit & Easy Sizing - Designed for a 10" x 18" or 18" x 10" duct opening (measured at the opening)

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

+ Product Details Size – 28"w X 18"h is the size for the duct opening measurement only

actual front end outer dimensions are approximately 22 5/8" width X 24 5/8" height

actual front end outer dimensions are approximately 12 5/8" width X 24 5/8" height

30" x 10" Cube Core Eggcrate Return Air Filter Grille for 1" Filter 18" Round Duct Pipe + Product Details Perfect Fit+ Product Details Perfect Fit & Easy Sizing Designed for a 30" x 10" OR 10" x 30" duct opening (measured at the opening), with actual outer dimensions of 32. 5" W x 12. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 29. 75" x 9. 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