A small RAR archive, about 506 KB, for the Xiaomi Mi 1S phone. The file name provides only the model, with no document type or board revision, so look inside before relying on it. Its size is similar to the Mi 1S schematic ZIP also in the index, so it likely holds comparable circuit diagrams. A technician uses such pages to follow power rails, check charging and connector circuits, and find which component loads down a shorted line. Confirm the mainboard version against the drawings first.
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.