The electrical engineering industry in the period prior to the first world war saw the spread of incandescent lamps. From the improvement of this invention, dating back to the nineteenth century, in 1905 carl auer von welsbach invented the lamps with wolframium thread in the bulb; always to him the invention of the osram brand, obtained by combining the scientific names of osmio (os) and wolframio (ram), ie the two elements of common use for the manufacture of the filaments of the bulbs, by virtue of their ability to hold the incandescence thanks to the very high fusion temperatures from (3000 to 3400 ° c). on 10 march 1906 the deutsche gasglühlumint-anstalt was then founded, holder of the osram brand rights, which was patented in berlin on 17 april 1906 (with the number 86924) for products such as "elektrische glüh- und bogenlichmpen". In 1919 the deutsche gasglühlumint-anstalt merged with siemens & halske and aeg: the company that named the name of osram werke gmbh kg. This piece is attributed to the mentioned designer/maker. It has no attribution mark and no official proof of authenticity, however it is well documented in design history. I take full responsibility for any authenticity issues arising from misattribution, european plug (up to 250v).the wiring of this item may be original and might need replacement, if not specified otherwise.