Very nice playing by this accordionist. He is actually playing a 5 row continental chromatic accordion.
The diatonic button accordions are usually 2 rows, 3 rows a lot of the time. The diatonic accordion is used a lot in Irish traditional music. The difference of the diatonic accordions are, each button will sound 2 different notes when you push and pull the bellows in or out, similar to a harmonica (blow and suck). The continental chromatic 5 row (and 4 rows in France sometimes) produces ONE note per button (the same as the piano accordion on each key). The 5 row accordion can have up to 102 buttons on the Righthand and 120 bass buttons similar to PA on Lefthand. It's RH keyboard layout is much more complex than the diatonic and difficult to play, but when mastered, the player can handle more complex music from classical to French musette.

Just saying.