7‑Zip can extract split RARs but cannot multi‑part RAR archives. It can, however, create split 7‑zip archives ( .7z.001 , .7z.002 ). To create a split RAR, you need WinRAR or the command‑line rar tool (available from the RARLab website).
If you have .rev files:
This is either a placeholder in documentation or an actual filename used to anonymize/hash the content. The length and randomness make it harder for search engines and bots to identify the file’s purpose. XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX.part2.rar
Without recovery volumes, your only option is to obtain the missing part from the original source. 7‑Zip can extract split RARs but cannot multi‑part