RAR archive simply titled N4020, with no board number, graphics variant or revision stated in the name. The 721 KB size suggests a schematic or boardview package for a mainboard of that model. Without more detail, open the contents and compare the ODM project code against the label on the actual board before using it to measure rails, find shorts or identify components. Extract it with WinRAR or 7-Zip and open the documents in a suitable PDF or boardview program.
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 @IT_SERVICE_WORLD. 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.