Package's weight corresponding to the PackageIndex .
This property is returned by UPS Server when the TrackShipment method is called. If the shipment contains only one package (PackageCount=1), this is the same as PackageWeight. This is set to 0 for package type of letters.
To retrieve this property corresponding to each package, the PackageIndex should be set from 0 to PackageCount - 1.
This property is read-only.