... transfer 4. Support DDNS IP modem, RS232 modem, GSM IP modem, GPRS data modem, data terminal,GPRS ... , Support transparent data transfe, gprs ip modem, gsm modemgprs modem with rs232 rs485 io for m2m meter ... , compatible 2 pulse wave output channels, 2 analog inputs and one pulse input counters.Support multi ... GSM1800MHz, GSM850/900/1800/1900MHz(optional)Compliant to GSM phase 2/2+GPRS class 10, class 12 ...