Valet - System One - Features Room to Room Communication - allows you to talk with people in other rooms of the home. Hands Free Reply - When being spoken to from another room, you can answer without interrupting what you were doing. You can respond “hands-free”. Door Answering Capabilities with 9 Built-In Door Chimes - Allows you to answer the door from any room of the house that has a room station. Person at the door can respond “hands-free”. Group Page/All-Call - Allows you to communicate with all room stations at one time. Private Call Function - Lets you talk privately to just one room station. Monitoring Function - Listen in on children playing or sleeping babies without them hearing you. Audio Input Jacks - Allows you to add & control audio output of an AM/FM radio, CD player, tape player, or MP3 player. Backlit Keypad - Makes it possible for you to operate the intercom even if the lights are off. Auto Programming - Once initial programming has been done, the room stations will reset themselves in the event of a power failure or electricity outage. Optional Auxiliary Board - With this optional feature, you can add home automation. Optional features include operating lights, air conditioning, gate/door release, garage doors, or numerous other devices, all with the touch of a button from any room station.