Tiny RAR archive of 26.4 KB with the uninformative name SIGNATURE NEW, carrying no brand, model or board number. The small size rules out a schematic or full firmware image; it may contain a signature, key or small configuration file, but this cannot be confirmed from the name alone. Open and inspect it before use, ideally scanning the contents for malware. If it is meant for a firmware or service tool, check which device and software version it targets before applying it to any board.
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 @ITHINKHS. 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.