Archive named for the ASUS Sabertooth Z97 Mark S motherboard, 660 KB in RAR format, with its contents not stated in the name. The small size suggests a boardview or similar document rather than a full BIOS dump, so check what is inside after extraction. Boardview data helps locate components, test points and nets when diagnosing shorts or missing rails. Confirm the board is the Mark S variant and check the revision on the PCB before relying on the data.
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 @boardview. 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.
7-ZipWinRARThe Unarchiver (macOS)