which file do I have to upload for updating the LTE5398-M904 router firmware?

technically what are the steps to follow? If I read the instructions:

"Default Settings in Firmware

• Refer to the *.rom in the fw release package.
• readable default configuration.
•  *.config define the default value of writable parameters, *.predef define the default value of read only parameters.
•  Please use the website http://jsoneditoronline.org/ to open the *.config and *predef files.

I don't understand because I downloaded the new firmware (v.3) but I see only a .bin file.

Thank you for help