Since 1949, TMI’s expertise in manufacturing quality transformers and magnetic products has enabled us to solve problems for our customers while meeting or exceeding their specifications and requirements. We manufacture custom-designed power, audio, choke, toroid, and printed circuit-mounted transformers for a wide range of industries. Transformer manufacturing is our core business and all products are proudly made in America. TMI serves the global market from our facilities centrally located in the Chicago transportation hub.