For use on an analogue connection, 2 single button access memory can also be used as function buttons, 10 additional programmable memory locations (or function buttons), Last number redial stoeres the last number dialled automatically, so it maybe redialled if the called number is engaged, Recall Button, to make an enquiry call or transfer a call Mute button, this will mute the microphone so that a conversation cannot be overheard, Ringer volume, Desk/Wall mountable, Available colours: black or silver