12" x 18" or 18" x 12" Cube Core Eggcrate Return Air Filter Grille for 1" Filter - Aluminum - White [Outer Dimensions: 14.5" X 20.5"] 18" Round Duct Pipe Its elegant look and fine

Its elegant look and fine finish and the natural warmth of oak wood

making it adaptable to various airflow needs

Outer Dimensions Are 17

Ideal for Walls & Ceilings: Designed for seamless installation in standard 14" X 8" duct openings

75"H – fits a 10" X 4" duct opening

12" x 18" or 18" x 12" Cube Core Eggcrate Return Air Filter Grille for 1" Filter - Aluminum - White [Outer Dimensions: 14.5" X 20.5"] 18" Round Duct Pipe Its elegant look and fine+ Product Details Perfect Fit & Easy Sizing Designed for a 12" x 18" or 18" x 12" duct opening (measured at the opening), with actual outer dimensions of 14. 5" W x 20. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 11. 75" x 17. 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