By using Portech SBK-32 expander for 32 SIM-cards, you can increase the number of channels in the Portech MV-37X GSM VoIP gateway series using the Internet.
We are one of the leading wholesale VoIP Termination service providers in UK providing an efficient and most reliable VoIP service to Calling Card Companies, Call Shops, Call Centers, ISP/ITSP, Business Enterprise and more.