30" x 10" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Grille Actual Filter Size – 17

Actual Filter Size – 17 3/4"w x 31 3/4" x 1"

actual front end outer dimensions are 37

With a 8" diameter for the duct opening measurement

Actual Filter Size – 15 3/4"w x 25 3/4" x 1"

30" x 10" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Grille Actual Filter Size – 17+ Product Details Perfect Fit & Easy Sizing Designed for a 30" x 10" OR 10" x 30" duct opening (measured at the opening), with actual outer dimensions of 32. 5" W x 12. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 29. 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