RAR archive named only with the code 5MMS-RH-01, with no brand or model given, so its device cannot be confirmed from the name. Codes in this style often look like a part or revision identifier, but that cannot be verified here. At 1.49 MB it likely holds a firmware dump or a small document set. Unpack it and check the contents against the label or chip markings on your board. If it turns out to be a flash image, back up the original chip first and make sure the image size matches the flash capacity.
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 @schematicslaptop. 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.