Help:Models Pages
The same thing done for brands is true for pages dedicated to models, which have their own structure and their own categorization, again to create a new page you copy the structure of an existing page, in this case the code to use for categorization is as follows:
[[Category:Modelli]] [[Category:Models]]
where again the second should be used only if the page has an English translation, and also in this case be careful to place it in any redirection pages, especially when different versions of a model are treated on the same page (as happens for example for the models 52, 54, 55, 56 and 58 of the Waterman that all point to the page Waterman 5x).
A further categorization of the models is that which sees them divided by brand, so to the previous indications you will have to add a further category referring to the brand, with something like that:
[[Category:Waterman]]
Anche in questo caso se si aggiungono dati cronologici si abbia cura di aggiornare le pagine della cronologia intervenendo sulla pagina relativa all'anno di cui si vuole registrare l'evento.