12" x 16" or 16" x 12" Cube Core Eggcrate Return Air Filter Grille for 1" Filter - Aluminum - White [Outer Dimensions: 14.5" X 18.5"] Ceiling + Product Details Size –

+ Product Details Size – 25"w X 18"h is the size for the duct opening measurement only

With a 5" diameter for the duct opening measurement

Ideal for Walls & Ceilings: Designed for seamless installation in standard 12" X 6" duct openings

with actual outer dimensions of 22

75"H – fits a 20" X 20" duct opening

12" x 16" or 16" x 12" Cube Core Eggcrate Return Air Filter Grille for 1" Filter - Aluminum - White [Outer Dimensions: 14.5" X 18.5"] Ceiling + Product Details Size –+ Product Details Perfect Fit & Easy Sizing Designed for a 12" x 16" or 16" x 12" duct opening (measured at the opening), with actual outer dimensions of 14. 5" W x 18. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 11. 75" x 15. 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