Dear Greg Our  LX-2102 group telephone switch provides telephony resources shared by all  its internal extensions. It makes internal calls free of charge and saves  rental & user fee charged by phone line provider. Functionalities includes  recordable auto greeting, direct extension dialing, incoming call transfer,  caller ID display, Long distance call automatic authorization ,IVR voice and  8  peers simultaneous talking. You are welcome to ask any question in detail.  Information material can be available upon the request.  Please visit our website http://www.****.com/switch.asp    FOB PRICE  LX-2102  4+8      $ 100 (4CO lines x 8 extensions)   LX-2102  4+16     $ 130 (4CO lines x 16 extensions)   LX-2102  4+24     $ 160 (4CO lines x 24extensions)  FOB Shanghai, P.R.China weight:5Kg, size:25X44X5.5cm zhang****xie@yahoo.com