They are characterised by the Liguriansubstratum. While Legnanese is closer to the Milanese dialect, Bustocco is very similar to the modern Ligurian language. In fact, there is the unstressed vowel u at the end of masculine nouns and other words (e.g. Bustocco gatu, secu, coldu, büceu, candu = Legnanese gatt, secch, cald, bicér, quand) and the elimination of some intervocalic consonants (e.g. Bustocco lauà = Legnanese lavurà). In both dialects the stressed a sounds like a mix between a and o.
A comic theatral group called I Legnanesi uses Legnanese (with simplified grammar and lexicon heavily based on Italian) in its shows.