Precision filters have advantages such as large filtration area, high filtration efficiency, small pressure drop, and easy operation and maintenance, etc. Hence, they ensure smooth production and the normal operation of downstream devices by delicately filtering liquids and isolating impurities. Filtering cartridges are categorized into sintered stainless steel fiber, sintered stainless steel powder, multilayered sintered stainless steel net, sintered non-metal fiber, wire wound, foldaway membrane filtration, ceramics, sack type, and rough, medium, and fine air filtration, according to its medium, precision, pollutant quantity, acidity/basicity, temperature resistance, strength, and regeneration ability. Its highest filtration precision is as high as 0.3μm.