4 line Wireless Terminal 1)lock card,lock terminal 2)support polar-reverse,12 or 16 KHz pulse signal 3)support GPRS 4 line Wireless Terminal Unique Functions1,GSM cellular network outgoing.2,GSM cellular network incoming.3,DTMF Caller ID.4,Support secondary dial.5,Lock card, lock terminal.6,Send polarity reversal signal for billing meter while connection.7,Sending 12/16KHz pulse for billing meter ...