26" x 16" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Powder-Coated Size - 10"w X 10"h

Size - 10"w X 10"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

The back is completely insulated

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

+ Product Description Introducing our 18" Wooden Corner Baseboard Grille - a sophisticated addition to elevate your HVAC system and interior decor

26" x 16" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Powder-Coated Size - 10"w X 10"h+ 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