FRAG-12 and "The Special Cartridge Co LTD"

I just found that this company is/was marketing the 12GA HE round “FRAG-12” which is known for a while and underwent evolution over the time. Also it was marketed by companies with different names.
I do not know who exactly is behind all of them (if so) but here I have found a new (older/oldest) player in the game “The Special Cartridge Co LTD” (from the UK).

Does anybody know more about the background or has catalogs of them?
The web is not yielding much info on them. I guess they do not exist anymore or have changed name or were bought by some other company?

I dropped the entry on Frag-12 from Jane’s ammunition book some years ago, so I must have had information that it was no longer being marketed. You are right that this had a confusing history!

Alex,

You probably already have the following but just in case:

12 ga FRAG-12, HE-AP, HE-FA.pdf (651.6 KB)

Tony, thank you for the input!

Brian, thanks for the sheet! I saw it before but now when I checked I was unable to locate it (in my mess).