JBM24 Button Module overview:

The JBM24 Button Module extends the number of call appearances and feature buttons on the
Avaya J169/J179 IP Phone. Each button module provides 24 additional lines for incoming calls,
outgoing calls, autodialing, and calling features. The Avaya J169/J179 IP Phone supports up to
three button modules, and each button module can take both Stand and Wall mount positions
together with the phone.

The following list shows the typical uses for the JBM24 Button Module:
• Additional lines for calls bridges from one or more other extensions.
• Buttons to access switching additional features like call forwarding.