Product Categories: Metering

Product Territories: Alaska, California, Hawaii, Idaho, Montana, Nevada, Oregon, Utah, Washington, Wyoming


TSTM Inc. is an industry leading manufacturer of secondary voltage transformers. Across the United States, Investor-Owned Utilities, Electric Cooperatives, and Municipal Utilities, trust TSTM products for use in electric metering applications. Our unique line of products create a safe work environment, ensure revenue grade accuracy, and provide necessary component protection for utility, industrial, and commercial installations. Our products are manufactured and assembled in the USA.


  • VT Packs
  • VersaPack
  • AccuPack
  • Harnesses
  • Sockets
  • Enclosures
  • Auxiliary Transformers