Firmware archive apparently for the ASUS J1800I-C board; the name spells it J18001-C, most likely a typo for the I. The name gives no version, revision or flash size, and the RAR is 4.05 MB. Open it to check which image it contains and how large that image is before writing anything. When a corrupted BIOS leaves the board dead, the SPI flash chip is reprogrammed with an external programmer. Save the existing chip contents first and confirm the board model printed on the PCB matches.
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 →