What is the FFU? FFU,fan filter unit,is a fan with a High efficiency particulate air Filter or Ultra Low Penetration Air Filter filter at  its outlet.1200mm*1200mm or600mm*1200mm is its standard size. Generally speaking,all the FFU have three step in order to adjust the airflow in the clean room and save energy.The control module is always integrated in its body so you can control it easily,local or remote。 With the decline of FFU's noise,more and more FFU are being used in clean room which cleanliness is  Class 10 or Class 1.