The Ruck EMKI 7040 EC 21 is a 1‑phase inline mixed flow box fan designed for quiet, efficient, and reliable ventilation. It features an efficiency-optimized diagonal impeller with CFD-optimized aerodynamics to provide stable and consistent airflow. The fan is housed in soundproof galvanized sheet steel for durability and low operational noise. The removable fan unit allows easy access for maintenance and cleaning. Equipped with a high-efficiency EC motor, the fan offers stepless speed control for energy-efficient performance. Internal electronic temperature monitoring ensures safe and dependable operation. This fan is suitable for commercial, industrial, and general ventilation applications requiring low-noise, high-efficiency airflow.