Voigtländer Ultron 50mm f/2

Optically good condition, some internal dust, no fungus. Shutter is slow. 1950s lens. I've quickly added an M42x1 threads so you can use it on M42 focusing helicoids, BUT this is not M42 with correct flange range. So not true M42 mount. The threads are metal, but the rest of this makeshift adapter is 3D printed.