Pyco, Inc. Thermocouples & RTDs – PYCO has been a leading manufacturer of thermocouples and resistance temperature detector assemblies for over 40 years. We ship Thermocouples and RTDs worldwide! Request a Quote now or call us at 1-800-755-2883 for expert assistance. An all-American company, PYCO has solid working relationships with the world’s best engineering firms and manufacturers of industrial equipment. The expertise we provide to them is available to solve your temperature measurement requirements.