RAR archive associated with the Z37S, 2.21 MB in size. The name gives only the model or board code, without revision or details of the contents. Its size suggests documentation such as schematic pages rather than a lone firmware file, but you need to extract it to confirm. Schematics help you follow the power-on sequence, measure rails and find the source of a short. Check the board number printed on the mainboard so the documents match the actual hardware.
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.
7-ZipWinRARThe Unarchiver (macOS)