ZIP for the ZyXEL P-660HW-T1 v2 wireless ADSL router, only 225 bytes, which is far too small to contain a firmware image. Expect a text file, link or empty placeholder inside rather than usable data. The real firmware must come from a full-size package for the v2 hardware revision. Before flashing any image, check the revision on the device label, since v2 and v3 boards differ, and use the web interface or recovery bootloader with stable power until the router reboots.
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 .zip file
Compressed archive that every operating system opens without extra software.
Back up your own chip before writing any dump, and match the full board number and revision. Flashing guide →