1 Adopt dual mode CID chip, compatible with FSK/DTMF CID receiving and transferring. 2 Day/Night mode with real time clock / Timed reminder 3 99 Private Password 4 Hi-efficiency safe switching power, battery back-up interface 5 External music input / Broadcast call 6 Less Cost Routing 7 Expandable module design , Flexible and simple Expansion (min capacity:416 max: 848) 8 Program by Standard Phone / by PC, PC interface compatible with CDX charge software. 9 Keep 3000 charge data while power off 10 Program by Standard Phone / by PC, PC interface compatible with CDX charge software. 11 Two door-locks & four doorphones 12 Automatix Redialing 13 Tow OGM(each have three paragraphs total 20 sec.) 14 Keep call forwarding setting while power off 15 Multi groups eight-digite restriction numbers 16 Monitoring can be conducted both inside and outside lines 17 lntelligent Routing(LCR) 18 Four exts.groups 19 Call switch(call pick during conversation)