The .7z.001 extension indicates that a large file was compressed using 7-Zip and then sliced into smaller chunks. : This is likely the specific project or file name.
While modern versions of can natively open simple .7z files, they often struggle with split .001 segments. It is highly recommended to use a dedicated tool: S1 396.7z.001
: This identifies this specific file as Part 1 of a multi-part set. Step 1: Gather All the Parts S1 396.7z.001