@jmacdonald There a lot of things not documented on NetSuite, that does not mean they can't be done my general approach for weird things is: - Load the Record, then .getFields() (You see analyze all the fields on that record.) - record.getSublists() make a loop and for each sublist getSublistFields() (analyze see all the sublist fields...) - From there you should have enough info to try conventional or unconventional way to add that serial number...