The string is a specific file segment typically found in multi-part archive downloads (like .rar or .zip ) for Fallout 4 .
If you are looking at this specific version (1.10.50) for purposes:
This specific version of Fallout 4 was a notable update released by Bethesda to address specific bugs and stability issues.
Note that Bethesda released a "Next-Gen" update in 2024 (v1.10.980 and later), which significantly changed file structures. v1.10.50 is considered an older "pre-Next-Gen" build.
Large games like Fallout 4 (which can exceed 30–50 GB with all DLCs) are often split into smaller "parts" for easier uploading and downloading.
"Part 4" is functionally useless on its own. To extract the game, you must have all preceding and succeeding parts (Part 1, Part 2, Part 3, etc.) in the same folder.