Polycom TransTalk 9000-Series - Manual (Page 258)

Feature Reference
5-148
To transfer a call to a Calling Group:
1. While on a call, press the switchhook down once rapidly.
You hear intercom dial tone.
2. Dial 7 and a group number (1–4). You can hang up or stay on the line to
announce the call.
All available extensions in the Calling Group ring.