26" x 16" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Powder-Coated actual front end outer dimensions

actual front end outer dimensions are approximately 27 5/8" width X 32 5/8" height

Insulation – A thick blanket of fiberglass insulation provides you with an R-Value of 4

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

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

Ideal for Walls & Ceilings: Designed for seamless installation in standard 18" X 12" duct openings

26" x 16" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Powder-Coated actual front end outer dimensions+ Product Details Perfect Fit & Easy Sizing Designed for a 26" x 16" OR 16" x 26" duct opening (measured at the opening), with actual outer dimensions of 28. 5" W x 18. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 25. 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