Small RAR archive of 285 KB whose name, qrt 5 ac, gives very little to go on; it may refer to a QRT 5 AC outdoor wireless unit, but the brand and firmware version are not stated. Being typed as firmware, it most likely contains a flash image or update file for that device. Before use, open the archive and inspect the contents and any version strings with a hex editor. Compare the image size with the flash chip on the board, and always read and save the original chip contents before writing anything new.
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 @biosarchive. 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.
Back up your own chip before writing any dump, and match the full board number and revision. Flashing guide →