Original heating trade vintage catalog for THERMAL UNITS MANUFACTURING COMPANY. Main office and factory was located at 64 East 25 Street, Chicago, IL. Manufacturers of Heaters, Coolers, Compressors, Humidifying Units, Air Conditioners, Fans and Automatic Refrigerating Compressors. Disbound from a large 1936 industrial heating catalog, this unique old one page technical brochure would display wonderfully matted and framed. A marvelous addition to your retro heating equipment library.