1937 product brochures from Groen Mfg. Co., Inc. Fabricators of Chemical and Process Equipment. 4535 Armitage Ave., Chicago, Ill. Jacketed Kettles, Condensers, fractionating columns, heat exchangers, copper process kettles, etc. Excellent condition. They come with a cover letter from the sales department replying to an interested customer in Boone, Iowa. 11" X 8 1/2". Groen is still in business producing commercial kitchen equipment.