Greeting the caller, reporting that all the operators are busy at the moment, plays music during waiting in queue, requests to stay on the line as the next available operator will pick up exactly your call.
Putting the call on hold by pressing the “Flash” button; the holding time is not limited. The function could be easily used at the moment when the second call has entered the line. By pressing the hold button the conversation will be set on pause and another call can be answered, finishing which you can return to the one which is on the pause mode.