The samsung ds5021d is a 21 button digital handset with a 16 character 2 line scrollable lcd screen features built in speakerphone 5 fixed function keys 21 programmable keys with tri coloured led status indicators which can function as dss direct station select keys and easy to use navigation keys to simplify telephone use this digital telephone is intended to be connected to a digital extension of a samsung dcs idcs or officeserv telephone system it is not intended