Like all other vehicles, ships too are identified by a code consisting of numbers and letters, called the foli. The first part of this code identifies the list to which the vessel belongs, which indicates for the purpose it serves. The letters that follow tell us in which maritime province it was built. The last numbers indicate the register folium in which the vessel in question is entered.
In this case, the foli corresponds to the coastal trade ship Aventina Masiques, one of the last devoted to cabotage in the sea around the Ebre Delta.