U.S.Robotics R24.0584.00 Guide De L'utilisateur page 22

Placing a call on hold
If you receive a call when you are already engaged in
another call, you can place the first call on hold to take the
second call.
Press send to take the incoming call and place the first
call on hold.
Press the contact button to switch to the incoming call.
Press send to talk.
Press end to end the active call.
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