Files named in this specific format (Early Access + part numbers) often originate from third-party file-sharing sites or repackers.
If you are looking for this specific update, the most stable way to get the full, current content is through the . Since SCUM is an Early Access title, it receives frequent patches that make older "parts" like this one obsolete and incompatible with official servers. SCUM.GOING.NUCLEAR.Early.Access.part04.rar
You cannot extract or use part04.rar on its own; it will result in a "missing volume" error. Files named in this specific format (Early Access