18" x 10" Cube Core Eggcrate Return Air Filter Grille for 1" Filter flat stamped steel + Product Details Perfect Fit

+ Product Details Perfect Fit & Easy Sizing - Designed for a 24" x 32" OR 32" x 24" duct opening (measured at the opening)

+ Product Details Size - 18"w X 16"h is the size for the duct opening measurement only

actual front end outer dimensions are approximately 30 5/8" width X 22 5/8" height

this 4-way air vent diffuser allows you to precisely control airflow

+ Product Details Size - 32"w X 28"h is the size for the duct opening measurement only

18" x 10" Cube Core Eggcrate Return Air Filter Grille for 1" Filter flat stamped steel + Product Details Perfect Fit+ Product Details Perfect Fit & Easy Sizing Designed for a 18" x 10" OR 10" X 18" duct opening (measured at the opening), with actual outer dimensions of 20. 5" W x 10. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 17. 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