Digital Extension The Ericsson Dialog 4224 Operator system phone is a digital phone which only works when connected into a digital extension on an Ericsson telephone system. If you do not have an Ericsson telephone system then this phone will not work. There are a number of Ericsson systems that this phone will work with including the Ericsson MD110 BC11 or BC12 as well as the Ericsson MX-ONE. Large LCD System Phone The Ericsson 4224 Operator telephone has a very large 6 line backlit display to show letters & numbers. This is very useful if the user needs to see the information quickly & clearly. The system phone also has 4 soft keys that can be used to scroll & access the information that is on the display as well. The Ericsson 4224 system phone also has a number of programmable buttons that can be set to the user’s preference. This is beneficial as features that are accessed on a regular basis can be set to a one touch button. Expandable Key Panel & Full Handsfree Speech Also the Ericsson 4224 Operator telephone has the ability to have up to 4 extra key panels connected. These are the panels of 17 programmable feature keys that can slotted at the side of the phone. The System phone also has a full handsfree speakerphone that allows the user to talk to the other party with ought having to lift up the receiver.