Fed 100mm viewfinder
It was produced for the 6,3/100 mm Fed lens and fits the accessory shoe. The parallax adjusts itself when setting the distance. Some very rare viewfinders were numbered.
Known serial numbers:
10461 _________ Elnur Mehdiyev
10993 _________ Bull Halsey's collection
11135 _________ PYC collection
16576 _________ eBay
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