This customization allows users of Netsuite's Pick/Pack/Ship advanced fulfillment feature to automatically create and send an invoice when the order is shipped. Upon Fulfillment of a Sales Order, and based on the shipping cost and customer preferences, an invoice gets created and sent by email when the status reaches "shipped".
If you process a high number of orders, for instance through a Warehouse Management System integrated with NetSuite, you can skip having to generate the invoices.
A scheduled script checks for newly created item fulfillment records that have not yet been invoiced. Once shipped, the originating Sales Order is transformed to an invoice (or a cash sale, depending on the payment method).