The FW58 series of flow switches are used for visual and electrical checking of various liquids. Unique streamline structure, accurate and stable design, widely apply to monitor the flow of liquids in pipes and cooling and lubrication system in all kinds of large, medium, minimum devices, such as electric generating unit, electric motor unit, rolling mills, compressors, transfer system and so on. The instrument will output a control signal when the pre-set switching points are exceeded. In addition, they can be installed in any position, which makes installation much easier. Therefore, it can be widely applied to monitor industrial flow in a variety of industries, such as oil field and petroleum refining industry, chemical and ethylene plants, pharmaceutical and metallurgical industries, power plant and paper mill, food products and wine factories, light industry and textile industry, industrial welding and water disposal industries, etc.