This is an early variation of FED 1a with smooth covering instead of textured vulcanite. The example shown may have a non-origonal, 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).
This cover exists on others FEDs to. No. 491 and 607 has the same.
Known serial numbers:
# 0058 ___ ? _________ preseries# 155 ____ no lens ___ seen on ebay
# 173 ____ ? _________ Photo Arsenal
# 253 ____ ? _________ private collection
# 316 ____ ? _________ Знание и Труд 1936 #4
# 389 ____ 389 _______ totally black, matte cover - private collection Russia
# 489 ____ ? _________ DVD Technik
# 491 ____ 491 _______ private collection Russia
# 508 ____ 508 _______ private collection Russia
# 575 ____ ? _________ private collection
# 608 ____ ? _________ pictures shown
# 911 ____ 911 _______ Alexey Nikitin
# 968 ____ ? _________ 1200 cameras