Cisco Ip Phone 8800 Series Administration Guide For Cisco Unified Communications Manager - Cisco 8800 Series Administration Manual

Connect Two or Three Key Expansion Modules to a Cisco IP Phone
Step 7 Connect the other end of the spine connector to the key expansion module as shown in this diagram.
a) Align the spine connector with the key expansion module accessory connector ports.
b) Firmly press the key expansion module into the spine connector.

Cisco IP Phone 8800 Series Administration Guide for Cisco Unified Communications Manager

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