Compressed archive of 2.17 MB labelled 3AESV-RH-10, the earliest of the 3AESV revisions in this set, judging by the RH-10 suffix. No brand or model is given and the payload type is unknown until it is extracted with WinRAR or 7-Zip. Material for a board revision is normally used to reflash a BIOS chip or trace circuits during repair. Make sure the revision on your motherboard really is RH-10. Back up the original SPI chip before programming, and check that the dump size matches its 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 @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.