Патрон-«жулик»

Вижу перевернутый ранний логотип чешского производителя Elektro Praga, так что страна тут не СССР. Я думаю этот переходник даже более ранний, чем указано. Возможно 1940-е или даже ранее.

В известном виртуальном музее про этого изготовителя написано следующее

Цитата:

Elektro Praga. In 1868 Gustav Kramer and Adalbert Löbl started production of refined glass and crystal lamps and chandeliers in Jablonec nad Nisou (Gablonz in the Austro-Hungarian Empire).
In 1908 they started production of accessories related to electric lighting, as sockets, plugs and switches. It proved to be a profitable market. Glass production was scaled down and ended in 1924. The company was renamed Kramer und Löbl, Fabrik elektrotechnischer Artikel (top left logo). In 1931 Kramer and Löbl introduced the Bakelite molding process in Czechoslovakia. The company became the dominant manufacturer of electrical accessories and exported products to many countries all over the world.
After annexation of Czechoslovakia in 1939 by Nazi Germany, the company was confiscated. From 1940 production was fully focused on war industry. After World War II, industry was nationalized in Czechoslovakia. Electro-technical companies were merged and renamed to Elektro-Praga. The plant in Jablonec nad Nisou had the monopoly for manufacturing electrical accessories. In 1989 state owned enterprises were privatized. In 1993 Elektro-Praga in Jablonec nad Nisou became part of the Asea Brown Boveri (ABB) concern.

Вот этот "верхний левый логотип", про который идет речь в тексте - как раз и вижу на изделии. Наверное эта штука ещё довоенная и даже ещё не Elektro Praga, а более ранее название.