Call Park

its setup out of the box. extension 700 is the parking attendant and will speak the parking slot number assigned to the calling channel. So you have a caller you want to park, you hit the transfer option on the phone to do an attended transfer, you dial 700 and the system says something like "Seven Zero One" and begins playing music, you complete the attended transfer specific to the phone's operation. The call is parked on 701. Someone from any phone can dial 701 to retrieve the call.