... 2.2 Slot 3. PSTN, Phone, CDMA, GSM Support 4.DTMF Detection 5.Factory ... Features:1,Support the access of wireless (GSM ), PSTN, Phone. 2,Supports GSM, CDMA two kinds of wireless communication ... standard. 3,Support GSM: 850M/900M/1800M/1900M ... each channel. GSM800 realize the integrate of Wireless(GSM or CDMA) and PSTN. 3, High security ...