20" x 18" Cube Core Eggcrate Return Air Filter Grille for 1" Filter w25h25 + Product Details Perfect Fit

+ Product Details Perfect Fit & Easy Sizing - Designed for a 8" x 20" or 20" x 8" duct opening (measured at the opening)

Rigid Gauge Steel

strong aluminum construction with smooth finished edges for easy and safe use

but still light and handy

+ Product Details Perfect Fit & Easy Sizing - Designed for a 16" x 30" OR 30" X 16" duct opening (measured at the opening)

20" x 18" Cube Core Eggcrate Return Air Filter Grille for 1" Filter w25h25 + Product Details Perfect Fit+ Product Details Perfect Fit & Easy Sizing Designed for a 20" x 18" OR 18" x 20" duct opening (measured at the opening), with actual outer dimensions of 22. 5" W x 20. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 19. 75" x 17. 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