[Nikon D300 + Tokina 12-24/4] c/n given on the display plate in the museum as AO118 and by Air-Britain Archive Special No. 5 as 1181, but both are not valid Mi-1 c/ns; if c/n 1811 was correct then it would point to the factory at Rostov as the producer as the highest known buikt there ends 1810 and was mfd jan61 where this was rgd feb61 so that slots in nicely