30" x 36" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Insulated Line 360-Degree Airflow: Experience optimal air

360-Degree Airflow: Experience optimal air circulation like never before

Ideal for Walls & Ceilings: Designed for seamless installation in standard 20" X 12" duct openings

rated at R3

+ Product Details Perfect Fit & Easy Sizing - Designed for a 16" x 14" OR 14" X 16" duct opening (measured at the opening)

30" x 36" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Insulated Line 360-Degree Airflow: Experience optimal air+ Product Details Perfect Fit & Easy Sizing Designed for a 30" x 36" OR 36" x 30" duct opening (measured at the opening), with actual outer dimensions of 32. 5" W x 38. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 29. 75" x 35. 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