14" x 36" or 36" x 14" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Compatible With Duct 6in 5" - SEE BELOW IN

5" - SEE BELOW IN DESCRIPTION HOW TO MEASURE A GRILLE

+ Product Details Size - 12" X 12" is the size for the duct opening measurement only

+ Product Details Size - 6"w X 20"h is the size for the duct opening measurement only

+ Product Details Size - The listed 5" diameter refers specifically to the size of the duct opening

14" x 36" or 36" x 14" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Compatible With Duct 6in 5" - SEE BELOW IN+ Product Details Perfect Fit & Easy Sizing Designed for a 14" x 36" OR 36" X 14" duct opening (measured at the opening), with actual outer dimensions of 16. 5" W x 38. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 13. 75" x 35. 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