Avaya Communication Manager Administrator's Manual page 610

Telephone Reference
6424D+ telephone
The 6424D+ telephone is a multi-appearance digital telephone with 24 call appearance/feature
buttons. With the 6424D+ telephone the end-user can access 12 features with the softkeys and
display control buttons. These 12 features can be used in addition to the features you assign to
the call appearance/feature buttons.
The 6424D+ telephone can work in both 4-wire and 2-wire environments.
Note:
You can connect an XM24 expansion module to a 6424D+ telephone to expand
Note:
the number of buttons you can assign. However, when the expansion module is
connected, you must connect an auxiliary power supply to the telephone.
6424D+M telephone
The 6424D+M telephone is similar to the 6424D, but with modular capabilities. You can install a
module in the telephone's desktop stand for increased set functionality. Note that these
modules can only be used in the desktop position; they cannot be used if the telephone is
wall-mounted.
610 Administrator Guide for Avaya Communication Manager