A RAR archive of about 1.32 MB labelled for the Xiaomi Mi 4 smartphone. The name does not describe the contents, so it may hold schematics, a board layout or other service documents. Extract it and check the files before relying on them. Material of this size for a phone usually consists of circuit diagrams used to trace power and signal paths, find components on a shorted rail and read connector pinouts. Confirm the mainboard revision against the drawings. A near-identical file name points to a probable duplicate.
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.