... 16 KHz pulse signal 3)support GPRS 4 line GSM Fixed Wireless Terminal Unique Functions1,GSM cellular network outgoing.2,GSM cellular network ... Caller ID.4,Support secondary dial.5,Lock card, lock terminal.6,Send polarity reversal signal for billing meter while connection ... : 99.99%9,Insertion loss: ≤0.5dB 4 line GSM Fixed Wireless Terminal/FWT