The lens was made at CKBK (aka EKRAN) in 1970 (#700011).
It is for Konvas-2M or Kinor-35 camera (oct-19 mount).
Bit sophisticated focusing system. For example, you can focus it to infinity in 250mm mode only. In 25mm mode it focuses from few centimeters from front lens surface. It is not really macro lens since it's factor is about 1:5 (you see 10cm wide object at maximum magnification).
Quite used condition. There are few dust particles inside, but I think that it will not benefit too much from cleaning. That is why I prefer to sell it as is. But if you insist, we can clean it for $50 extra.
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