This is an early variation of FED 1a with smooth plastic covering instead of textured vulcanite. The example shown may have a non-original, replaced covering, as existing photos and examples in collections have a smooth black covering that is much less shiny, showing an almost matte surface (please see the black and white archival photo). Camera FED #508 is completely authentic! Personally, I held her in my hands!/A.Nikitin/
There are also a Fed 1c #71648 and a Fed 1d #157514 listed with a smooth black cover, so it seems there must have been kind of cover replacements. All covers including the vulcanites on these early Fed 1 are leaves, the cut of the leaf can be seen below the lens mount. The finish of the hole on the backside can help to determine if a cover is not original.
Serial number range: #0031 to 9xx
Known serial numbers are listed in the general Fed 1a entry.
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