... reverse,12 or 16 KHz pulse signal 3)support GPRS 4 line Wireless Terminal Unique Functions1,GSM ... GSM cellular network incoming.3,DTMF Caller ID.4,Support secondary dial.5,Lock card, lock terminal.6, ... pulse for billing meter while connection is also compatible.8,Support GPRS . (Optional)9,Rechargeable battery, keep conversation for ... Insertion loss: ≤0.5dB 4 line Wireless Terminal/Fixed wireless terminal