12" x 30" or 30" x 12" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Compatible With Duct 8in + How To Measure A

+ How To Measure A Grille Overall Size:

+ Product Details Size – 18"w X 28"h is the size for the duct opening measurement only

efficient airflow

+ Product Details Perfect Fit & Easy Sizing - Designed for a 24" x 36" OR 36" x 24" duct opening (measured at the opening)

12" x 30" or 30" x 12" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Compatible With Duct 8in + How To Measure A+ Product Details Perfect Fit & Easy Sizing Designed for a 12" x 30" or 30" x 12" duct opening (measured at the opening), with actual outer dimensions of 14. 5" W x 32. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 11. 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