ESF constant power electric heating tapes in series are generally suitable for temperature maintenance and antifreeze protection of pipelines and equipment in hazardous areas. In particular, they provide an excellent solution for situations where the pipeline is too long and exceeds the maximum loop length allowed by the self-limiting temperature heating tapes and parallel constant power heating tapes. This product has corresponding products with single-core (1ESF), double-core (2ESF) and three-core (3ESF) structures, and each product has subdivided specifications with different resistance levels, so it can meet the requirements of different voltage levels and different electrical connection forms, and can meet the heating needs of pipelines or equipment of different forms and lengths. At the same time, this product also has the best chemical resistance and good mechanical structure, so it is widely used.