Basic components of the FFU are including fans, cover, pre-filters, high-efficiency or ultra-high-efficiency filters, airflow equalization devices and electrical control elements, etc. · Electrical control element is an important guarantee for FFU automation and energy saving. ·Standard size for a FFU are 1200x600mm, 1200x900mm,1200x1200mm, and some non-standard size as requirements. ·According to the motor form