R-13 wall lamps from the house Raak Amsterdam, from 1968, in metal and aluminum shade. The model was created in a 220 V transformer spot, and as applied here. Below, the original documentation translated by me and my colleague google translation.
"The R-13 projector is the result of the teamwork of our optical and tool market specialists, on the one hand, a sophisticated theory of" dual optics ", and on the other, the realization difficult and extremely precise molds "