It is common for individual modders to name their personal working files with shorthand (e.g., initials + date).
if the source is unknown, as .7z files can contain "zip bombs" (files that expand to terabytes of data to crash a system) or executable malware.
The .7z format is the gold standard for (like those for Skyrim , Assetto Corsa , or Minecraft ) because of its high compression ratio.