Yeastar TG is a series of VoIP 4G gateway connecting 4G LTE network to VoIP network directly and can support two-way communication: 4G to VoIP or VoIP to 4G. It is the best 4G trunking solution for IP-based telephone systems, the best fallback solution in case of landlines outages, and the best alternative for areas with limited landline or SIP connection. TG200: 2 4G Channels* TG400: 4 4G Channels* TG800: 8 4G Channels* TG1600: 16 4G Channels*