26" x 26" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Color_Red Oak Actual Filter Size – 13

Actual Filter Size – 13 3/4"w x 15 3/4" x 1"

The lightweight yet rigid construction ensures durability without sacrificing ease of handling

+ Product Details Size - 28"w X 10"h is the size for the duct opening measurement only

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

Tamper-Proof Design – Provides robust protection to prevent unauthorized access and ensure consistent thermostat settings

26" x 26" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Color_Red Oak Actual Filter Size – 13+ 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