If the user chooses to add a number in the PARCELS field when forwarding to a supplier shipping advise (SSA), this will decide the number of labels printed, but without serial numbers as they will not always match the quantity vs the serial numbers defined. 

If the PARCELS field is left empty, one label per serial number will be printed and the serial number is included on the label.  

If the PARCELS field has the value 0 - no label will be printed.