34" x 10" Cube Core Eggcrate Return Air Filter Grille for 1" Filter w8h8 It has an outer surface

It has an outer surface made of high-quality aluminum foil and an inner surface made of metalized PET with inside high-tensile spring steel wire

Total outer size of this grille is

designed to distribute air evenly throughout your space

+ Product Details Size – 14"w X 2"h is the size for the duct opening measurement only

+ Product Details Size - 20"w X 2"h is the size for the duct opening measurement only

34" x 10" Cube Core Eggcrate Return Air Filter Grille for 1" Filter w8h8 It has an outer surface+ Product Details Perfect Fit & Easy Sizing Designed for a 34" x 10" Or 10" x 34" duct opening (measured at the opening), with actual outer dimensions of 36. 5" W x 12. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 33. 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