Xiaomi Mi 4 service archive in RAR format, about 1.32 MB, whose name differs from another file only by a trailing space, so the two are likely duplicates. No contents, board number or revision are stated, so unpack it and look inside before use. Archives of this kind for phones typically carry schematic PDFs that let a technician follow supply rails, test charging circuits and identify parts around a faulty connector. Match the board markings to the documents before making measurements or replacing components.
The button opens the matching file on RM Schematics, or a source page if it is not catalogued there yet. The original attachment is from @cyberlanelectonik. Enginerys does not host this file.
How to open a .rar file
Compressed archive — the usual wrapper for a schematic + boardview pair or a BIOS + EC set.