Automatic Temperature Regulating Agent Series is a kind of thermal expansion materials, which depends on principles that the substance expands when it is heated and constricts when it is cooled and a liquid is incompressible. It can automatically regulate temperature. When the ambient temperature goes up to the special value, Automatic Temperature Regulating Agent goes up to the special temperature with the ambient temperature, its unit volume increases. When the ambient temperature falls down to special value, Automatic Temperature Regulating Agent also falls down to the special temperature with the ambient temperature, its unit volume reduces. The agent is loaded in the purpose-made thermostatic element. The variation of ambient temperature takes a pressure and the thermostatic element takes a change, and this change brings the movement of either the appurtenance of the thermodynamic component or itself, thereby carrying out the automatic opening & closing function. All sorts of temperature controllers and the electrical switches are developed depending on the physical feature of Automatic Temperature Regulating Agent. It has been widely used in the fields of refrigeration, auto-control system, automobile industry, petrochemical industry, sanitary ware, heating and ventilating, electric electron, building, space & aviation etc.