10" x 34" or 34" x 10" Cube Core Eggcrate Return Air Filter Grille for 1" Filter - Aluminum - White [Outer Dimensions: 12.5" X 36.5"] 2-Way + Product Details Perfect Fit

+ Product Details Perfect Fit & Easy Sizing - Designed for a 18" x 26" OR 26" x 18" duct opening (measured at the opening)

actual front end outer dimensions are approximately 7

Performance – High diffusion induction rates result in rapid temperature and velocity equalization of the mixed air mass well above the zone of occupancy

Actual Filter Size – 7 3/4"w x 33 3/4" x 1"

10" x 34" or 34" x 10" Cube Core Eggcrate Return Air Filter Grille for 1" Filter - Aluminum - White [Outer Dimensions: 12.5" X 36.5"] 2-Way + Product Details Perfect Fit+ Product Details Perfect Fit & Easy Sizing Designed for a 10" x 34" or 34" x 10" duct opening (measured at the opening), with actual outer dimensions of 12. 5" W x 36. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 9. 75" x 33. 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