Also if you go to a Sales Order and you click Print Picking Ticket you will notice the URL something like this: https://system.na2.netsuite.com/app/accounting/print/hotprint.nl?regular=T&sethotprinter=T&template=133&id=4539167&label=Picking+Ticket&printtype=pickingticket&trantype=salesord

Yes, Its basically comes from Advanced PDF/HTML Templates Preferred Picking Ticket