... port(TxD, RxD, RTS, CTS, DTR, DSR, DCD, GND), rate speed up to 230400 BPS;Supports PAP authentication and CHAP ... heartbeat technology to keep application layer stable connection;Success rate of registering GPRS Network once power on is 100%; ... Voltage12VDCPower ConsumptionStandby145~65Ma; Registering GPRS Netork:225~65Ma; Transfer data:265~285Ma;GPRS NetworkFrequency: 850 MHz, 900 MHz,1800 MHz ...