Original electrical trade vintage catalog for KEYSTONE ELECTRIC MANUFACTURING COMPANY, was located at Janney and Tioga Streets, Philadelphia, PA. Manufacturers of Fluorescent lighting for commercial, residential and industrial. Keystone PK-296 and PK-496, PK-240, AW424, R-496. Disbound from a large 1949 electrical construction materials book, this unique old one page technical specifications brochure would display wonderfully matted and framed. A marvelous addition to your retro lighting equipment library.