It runs on a Linux-based proprietary OS. Over the years, ZTE released firmware versions like V2.30, V5.0, V6.0, and finally . The "V80" build was the last major stabilization release for legacy hardware before ZTE moved to the F680 and F609 models.
Installation (general steps — may vary by build): zte f660 firmware v80 fixed download
Click 'Upgrade'. The process usually takes 3 to 5 minutes. The device will reboot automatically once finished. It runs on a Linux-based proprietary OS
: Includes support for IPv4/IPv6 Dual Stack and DS-Lite, ensuring the device is future-proof as networks migrate away from IPv4. Enhanced QoS Engine ZTE released firmware versions like V2.30
: Select the downloaded firmware from your computer and click Upgrade .