34" x 18" Cube Core Eggcrate Return Air Filter Grille for 1" Filter w36h36 See our separate listing for

See our separate listing for Butterfly Dmaper to Control Airflow

positioning supply and return grills accordingly

875" width X 15

12"w X 3"h Is The Size For The Duct Opening Measurement Only

8" Diameter Is The Size For The Duct Opening Measurement Only

34" x 18" Cube Core Eggcrate Return Air Filter Grille for 1" Filter w36h36 See our separate listing for+ Product Details Perfect Fit & Easy Sizing Designed for a 34" x 18" Or 18" x 34" duct opening (measured at the opening), with actual outer dimensions of 36. 5" W x 20. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 33. 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