26" x 10" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Color_Aluminum + Product Details Size –

+ Product Details Size – 18"w X 12"h is the size for the duct opening measurement only

Horizontal performance assures confident use of cooling temperature differential of 30 degrees Fahrenheit and greater

4" X 14" Is The Size For The Duct Opening (floor/vent hole) Measurement Only

this thermostat guard is the perfect solution for safeguarding your temperature controls

actual front end outer dimensions are approximately 14 5/8" width X 10 5/8" height

26" x 10" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Color_Aluminum + Product Details Size –+ Product Details Perfect Fit & Easy Sizing Designed for a 26" x 10" OR 10" x 26" duct opening (measured at the opening), with actual outer dimensions of 28. 5" W x 12. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 25. 75" x 9. 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