Aastra M401 User Manual page 16

2.3 "SHUTTLE"
If you wish to switch from one party to the other:
Press the key
then
Press the key
You can speak to both parties, but they cannot speak with each other.
2.4 CONFERENCE CALL
If you wish to establish a three-party conference:
Press the key
then
Press the key
You have established a three-party conference. If one of the parties hangs up,
you remain connected to the remaining party.
R
2
R
3
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