PBX lines are enhanced to work with PBX Systems. Roll over (hunting) is included at no additional charge in most areas. PBX lines offer unlimited local calling.
The criteria for determining whether a multifunctional telephone system is to be considered a Key system or a PBX system will be based upon the following: Where the station user must selectively access which line is to be connected to that station in order to make a call, the use will be considered Key system usage. All other usage will be considered PBX system usage.