This lens belongs to the first series of Industar-22.
Inspired by the 3,5/50mm Fed lens, perhaps even with common parts, but with the new diaphragm scale.
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Princelle: K330
Fotoua: 1aR4
Marked: 50mm"."
Sign: small focus button
Formula: 4 elements in 3 groups
Glass: uncoated
Weight: 117g
The front of the lens is in aluminium and the diaphragm cursor is small.
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Photo 1: This lens was mounted on a Fed-Zorki 1948.
Serial number: 11558 (Jacques M. coll.).
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