Thanks Bob Bolton.

The 3 to 6 row, same note in and out, chromatics are called 'Chromaticas' ... by the italians, but nobody (much) else. they also come in at least 3 different schemes, with national preferences.

Are these the ones that I was referring to as 'continental chromatics'. That's the term I heard used for an accordion that is essentially the same as a piano accordion except with buttons on the treble side rather than keys.