The file indicates that a larger dataset, software, or collection of files (possibly named "SS-Nin-030_s") was broken into smaller, numbered parts (e.g., .001, .002, etc.) to make downloading or transferring easier.
7zip file with numbers on it like 001 means that you only have a part file of the whole compressed file. Microsoft Learn How to Open and Extract .001 Files - Microsoft Q&A SS-Nin-030_s.7z.001
You must use 7-Zip or WinRAR to open the first file (.001) and extract the entire content. The file indicates that a larger dataset, software,