Unlike Parker, Sheaffer did not play much with orange celluloid. Still at least three pens and four pencils are catalogued in orange plastic, what Sheaffer eventually called Coral (not to be confused with tthe two-tone Coral used by Wahl, Carter and others).
A mini collection of Coral Sheaffer plastic flat top pens thus would seem to be a modest undertaking. Indeed I really never set out to find these with a completist bent. Over the years I've even sold pens that were not duplicates. Still, inexorably I seemed to have ever more of these resting in the pen cabinet. Then I started finding the off-catalogue variants. That sort of discovery is my collecting sweet spot. Indeed, I might be responsible for introducing to the hobby-at-large the notion of the slender orange Sheaffer plastic flat-top. Ahhh, fame.
I just tossed the collection in a tray for a quick photo shoot.
The six items at left all are catalogued and represent six of the seven catalogued sizes and trim configurations. One could double the pen count, recognizing that early pens had "46 Special" nibs and were considered pens of that line, while later pens had "3-25" nibs and indeed had that same imprint at top of cap. All the pens from the catalogued group are standard girth. An oversized pencil (no pen catalogued to match) starts the run at the very left. As the pens with the two different imprints look essentially the same, I have not felt the need to have duplicates of each pen just to have the two imprint sets.
The ten items at right all are undocumented to best of my knowledge. There are some weird pens amongst those ten. Some have "late" features which alone might lump them simply into the now recognized post-1929 flat-top category. Others have off-catalogue trim. The last five are the nifty slender pens, those again perhaps being my "discovery" for the hobby.
Later, when I'm actually awake, I can outline some more details of the odd pens at the right.
Other flat-top aficionados are invited to comments. Actually anyone is invited to comment
regards
david