Nice! It's also the 1875-S/S RPM and MPD FS-302.
If its flat and shelf like it's probably machine doubling. I know it's relatively common on quarters but I'm not so sure about nickels.
I don't see it on either variety Vista or Wexler. Do you mean the flatness at the bottom?
PRMS66
AU53 AU55
MS62
AU53
MS65BN
VF OR XF details if it has the central vertical jewels then XF.
O-108 XF45
VF25
MS65
MS65*
MS64*
MS64
AU58
MS66
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