Single phase and three phase pole mounted transformer. It can reduce the length of low-voltage distribution lines, reduce line losses, and improve the quality of power supply. The transformer is designed with high efficiency and energy-saving coil core structure. The transformer is characterized by small volume, small infrastructure investment, reduced radius of low-voltage power supply and more than 60% loss of low-voltage line. Adopts fully sealed structure, with strong overload capacity, high reliability of continuous operation and simple maintenance. It is suitable for rural power grid, remote mountainous areas, scattered villages, agricultural production, lighting and power consumption, and can also be used for energy-saving transformation of railway and urban power grid. Our transformer was designed with advanced technology and adopts high quality material and components which result in reliable quality and long operation time.