26" x 26" Cube Core Eggcrate Return Air Filter Grille for 1" Filter RG66 Black-HP + Product Details Size –

+ Product Details Size – 10"w X 4"h is the size for the duct opening measurement only

14"w X 6"h Is The Size For The Duct Opening Measurement Only

Made of High Quality Aluminum That Will Never Rust

you can watch this informative video tutorial: How to Measure Your Vent Hole Before Ordering a Grille

26" x 26" Cube Core Eggcrate Return Air Filter Grille for 1" Filter RG66 Black-HP + Product Details Size –+ Product Details Perfect Fit & Easy Sizing Designed for a 26" x 26" duct opening (measured at the opening), with actual outer dimensions of 28. 5" W x 28. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 25. 75" x 25. 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 Made from