Aastra Telecom 53I - Manual (Page 11)

Hardware Support
RN-001029-00, Rev 03, Release 2.1 5
5i Series IP Phone Release Notes
Hardware Support
53i Supports 536M Expansion Module
The 53i IP Phone now supports the optional 536M Expansion Module
(previously only supported on the 55i, 57i, and 57i CT). This module adds 36
additional softkeys to the IP phone. The 536M provides paper labels for each
softkey. Up to 3 modules can be piggy-backed to provide up to 108 additional
softkeys for the phone.
536M
Module
Expansion
536M
Module
Expansion