Comparing with different objects and different uses area, this series of product can be divided into three kinds for preliminary-effect. (used for >1-5 um dust), Medium-effect (used for 1-5 um dust), High-effect (used for <1-5 um dust ). The preliminary-effects be widely used for large oxygen producing machine, air pressure machine, and the air-conditioning system preliminary filtering of electronic, chemical, medicine, and automobile industry. The medium-effects be used for some common industrial and public places. And the High-effects also be widely for dustproof purified workshops of optical, electronic, LCD manufacturing, biomedical, precision instrument, beverage and food, and PCB printing industry. Detailed Product Description