01) GSM 850MHz 900MHz 1800MHz 1900MHz CDMA 450MHz 800MHz 1900MHz 02) Standard PSTN FXS with RJ-11 to telephone or voip gateway & PABX 03) 400-500Hz Dial-tone and Busy-tone , Disconnect Tone 04) 50V in idle and 75V in ringing and 9-12V in talking 05) DTMF detector in RJ-11 06) Provide reverse polarity 07) Caller ID (DTMF,after ONE Ring) to telephone or voip gateway or PABX Caller ID (FSK) to telephone or voip gateway & PABX(Optional) 08) One Number Unified 09) CLIR(Calling Line Identification Restriction) 10) Separate Power On/Off controller 11) LED indicating Hook On/Off,Talking,Signal Intensity,Power On/Off 12) Setable dialing delay time 13) Setable automatic dialing 14) Support to dial all number including of * # 15) DTMF Automaticly dialing to GSM , to voip gateway , PABX(Optional) 16) SPK & MIC volume regulate 17) Provide accumulator charger interface (Optional) 18) Multiparty Calling teleconference (Special Optional) 19) Setable Maxim talking time to warn of exchanger card (Special Optional) 20) 4SIM Rotator Automaticly (Special Optional) 21) IMEI changing (Special Optional) 22) Rasio Bases Changing Automaticly to simulate movement (Special Optional) 23) Simple to install and easy to maintain 24) Steady module & reliable design ensures good performance 25) Strong signals with high gain antenna 26) No noise & Clear voice 27) Suitable for wide voltage range & Low power consumption 28) Suitable for all kinds of weather & environment 29) Offer keypad command sets to define functions