26" x 12" Cube Core Eggcrate Return Air Filter Grille for 1" Filter 8" Diameter + Product Details Size –

+ Product Details Size – 34"w X 32"h is the size for the duct opening measurement only

Commercial Grade Aluminum - Will Never Rust - Designed for Warehouses

+ Product Details Size – 28"w X 6"h is the size for the duct opening measurement only

+ Product Details Perfect Fit & Easy Sizing - Designed for a 12" x 18" or 18" x 12" duct opening (measured at the opening)

+ Product Details Size - 22"w X 28"h is the size for the duct opening measurement only

26" x 12" Cube Core Eggcrate Return Air Filter Grille for 1" Filter 8" Diameter + Product Details Size –+ Product Details Perfect Fit & Easy Sizing Designed for a 26" x 12" OR 12" x 26" duct opening (measured at the opening), with actual outer dimensions of 28. 5" W x 14. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 25. 75" x 11. 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