RAR archive of 417 KB labelled as an hk9 conversion, most likely a guide for converting a board with a discrete graphics section to integrated (UMA) operation, although the name does not name the laptop brand or full board number. Such packs usually hold marked-up schematic pages, photos and a list of components to remove or bridge. Before using it, confirm that the board number and revision silkscreened on your PCB match the material inside, and keep the original BIOS backed up because conversions often need a UMA firmware image too.
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 @hrtechno. 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.