G.O.I. for Leica M 1.5/50mm Jupiter GOI Leningrad ca.1942

GOI Leningrad USSR 1942. very early Prototype one of the first famous Soviet "Jupiter-3" which were designed by the GOI 1941/42 and later post-war made by other Soviet factories and are still built by the KMZ today, uncoated clean glass only view lenses as a prototype made by GOI, modified to Leica M-mount for full format 24x36mm, a very fine minimale Small scratches on the front glass that did not affect the quality of the picture