Documentation set for a Quanta board labelled Miata 2.0 NM3 at revision 1A, provided as a 771 KB RAR archive. Miata reads as an internal platform codename and NM3 as the Quanta project code, while no retail brand or model is given. The contents are most likely a schematic, which a technician uses to trace rails, signals and connector pinouts while fault-finding. Check that the NM3 marking and revision 1A on the PCB match before using component values or reference designators from the file.
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.