Functionality:
Connects the PBX to two analog telephone lines (PSTN)
Enables users to make and receive external calls through the PSTN network
Suitable for areas with limited VoIP or SIP trunk access
Compatibility:
Compatible with Yeastar S20, S50, S100, and S300 PBX systems
Installs into available module slots within the PBX chassis
Use Cases:
Businesses needing backup lines in case of internet failure
Locations where PSTN is still in use
Integration with traditional landline infrastructure



