The Super Display Telephone, which is supported with software 1.07 or higher, is the system's premier telephone instrument, featuring an interactive 9-line, 24-character display with 12 associated interactive keys. As the Super Display Telephone user processes calls, the interactive key functions change to provide intuitive access to the system's most sophisticated features. Every Super Display Telephone has a built-in speakerphone for full Handsfree operation. Handsfree Answerback and Intercom voice-announce capability is also standard.      The telephone's 24 programmable function keys can be customized by the user for one-button access to co-workers, features like Paging or Park or specific outside lines. The Dual LEDs in each programmable key help the user see which calls are for them and which features are active. Access to other commonly used features is simplified by 15 fixed feature keys. In addition, the Super Display Telephone provides a built-in wall-mount bracket, as well as adjustable legs which allow each phone to be angled at a height which best suits the user. Note that the three IP adapters (IP, ADA2, and PSA) do not work on the Super Display Telephones.