 Once the mail is bar coded, it is automatically sorted by a Delivery Bar Code Sorter (DBCS) that reads the bar code, identifies the destination of the mailpiece, and sends it to an appropriate tray that corresponds to the next segment of its journey.Regional mail is either trucked to the appropriate local post office, or kept in the building for carrier routes served directly from the P&DC.Out-of-region mail is trucked to the airport and then flown, usually as baggage on commercial airlines, to the airport nearest the destination station.