Tianjin Sankai Weike Vacuum Switch Co., Ltd. (formerly Tianjin Sankai Vacuum Switch Co., Ltd.) was originally subordinated to Tianjin Mechanical and Electrical Industry Holding Group. It was restructured according to document No. 13 of Tianjin Computer Control Set [2001]. It was a professional manufacturer engaged in research and development and production of vacuum switches in the early 1970s.