The basic idea of these lights designed by Wilhelm Wagenfeld (sockets and bulbs) is to replace the trinity of socket, bulbs and light glass in favour of a duality of socket and bulb (newly designed for this purpose). In the porcelain socket, an ELROYAL bulb of opal glass is screwed in, which is a continuation of the slightly conic form of the socket. The flush mounting version of the socket was added at a later date (intended for installation in flush-mounting switch boxes). These designs by Wilhelm Wagenfeld were created in the early 1960s in the context of his then ELDECO lamp family. This included other specially designed lights, which Wagenfeld named ELROYAL, ELCORONA, ELREGENT and ELDEA. The opalescent version of the lighting is fully glare-free and thus ideally suited for mirror and other special lighting. This was a completely new, popular design element used by architects, planners and builders.