Unison phone system offers big business features to small businesses, such as extension status indicators, music on hold and digital receptionist. Expand your system up to 10 desk phones and handsets. Only one phone jack required. It’s easy just plug the Unison Base Station into any phone jack and wirelessly connect desk phones and handsets, only one phone jack required. Program the auto attendant with scheduled day/night modes. The full duplex speakerphone provides the utmost of clarity. There is a 200 name/number directory, 20 number speed dials and 99 name/number caller ID phone book and history.