Barnes & Jones was founded before the turn of the century by two engineers who applied their expertise to build quiet and efficient steam heating traps and systems. Today, Barnes & Jones manufactures 100% calibrated cage unit inserts, the recognized standard in the steam heating repair kit market, for every heating steam trap body ever made. Barnes & Jones products are available throughout North America, Central and South America, and most of Europe. The operating principle of these cage units, first introduced in 1902, remains unchanged as cage units emerge, today, as the preferred automatic valving solution for high-tech environmental control systems.