The Ericsson Dialog 4223 Professional features a three row adjustable graphic display, accommodates up to four key panels, as well as 13 keys with LEDs and four soft keys. Through these soft keys, the user can easily access the display menu with a number of system features such as phonebook, call list, diversion and absence reason. Line access 2 Inquiry key Programmable keys 4 Message Waiting Indicator Loudspeaker Mute function Volume control Programmable ringer volume Graphical display 24 x 39 pixels Connection for extra key panel 4 x 17 keys Hearing aid support with amplification 6dB