36" x 8" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Color_Red Oak Wood Easy Installation – Includes all

Easy Installation – Includes all necessary screws for quick and hassle-free setup

+ Product Details Size – 20"w X 18"h is the size for the duct opening measurement only

+ Product Details Perfect Fit & Easy Sizing - Designed for a 30" x 30" duct opening (measured at the opening)

+ Product Details Outer dimensions: 21

+ Product Details Size – 10"w X 16"h is the size for the duct opening measurement only

36" x 8" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Color_Red Oak Wood Easy Installation – Includes all+ Product Details Perfect Fit & Easy Sizing Designed for a 36" x 8" OR 8" x 36" duct opening (measured at the opening), with actual outer dimensions of 38. 5" W x 10. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 35. 75" x 7. 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