This product is an outer core reactor made with a unique oval winding process. Its external structure is made of superimposed overlapping silicon steel sheets the mechanical bearing capacity is strong and the structure is stable and rigid. Its structure has been calculated and analyzed to ensure that while maintaining functionality its overall weight being the lightest compare with other brand’s reactors of the same kind. It should be installed inside the cabinet and forced-air cooled. This series of products combine the advantages of stable inductance value of air-core reactors and small magnetic flux leakage of core reactors together. Its structure is simple. It has a wide range of application, which includes the next generation metro project.