26" x 30" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Compatible With Duct 12in Insulation density is 30kgs/cbm =

Insulation density is 30kgs/cbm = 0

Actual Filter Size – 31 3/4"w x 11 3/4" x 1"

Slots Are Angled to Diversify The Airflow In 2 Way Direction - Great for Wall and Floor & ceiling Applications

+ Product Details Perfect Fit & Easy Sizing - Designed for a 20" x 36" OR 36" x 20" duct opening (measured at the opening)

The total outer size of this grille is the listed size plus plus 2 and 5/8"

26" x 30" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Compatible With Duct 12in Insulation density is 30kgs/cbm =+ Product Details Perfect Fit & Easy Sizing Designed for a 26" x 30" OR 30" x 26" duct opening (measured at the opening), with actual outer dimensions of 28. 5" W x 32. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 25. 75" x 29. 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