An intercom, also called an intercommunication device, intercommunicator, or interphone, is a stand-alone voice communications system for use within a building, small collection of buildings or portably within a small coverage area, which functions independently of the public telephone network.

Caller ID System combinations:

Line In: 00 Line Out: 08
Line In: 02 Line Out: 08
Line In: 03 Line Out: 12
Line In: 04 Line Out: 16
Line In: 04 Line Out: 24
Line In: 04 Line Out: 32
Line In: 08 Line Out: 48
Line In: 08 Line Out: 64
Line In: 08 Line Out: 128
Line In: 00 Line Out: 128

Intercom System Components:

Intercom Exchange
Intercom Phone set
Telecom Cables
Modular Box
Telephone Patchcord and Faceplate.

Genaral Features:

* auto- extension number display
* boss/secretary call
* caller ID intercom
* call forwarding
* call pickup remotely
* conversation interrupt & break (operator phone)
* do not disturb
* extension flexible numbering "100"~"999"
* extension call duration control
* 3-party conference call
* auto-attendant 3-level 30seconds
* flash time setting
* music on hold (built-in & external)
* PC program & billing system
* power failure transfer
* 3-class anti-lightning protection
* 7-class of services