I have a Skel Activator with a Pellotes. The pellotes is a  plastic ball in the middle of the upper jaw plate which I believe is used to treat tongue thrust.
I think pellotes is a German word??

How sure are you?
I have several appliances with plastic guards either in front of or behind lips, and only one that was advertised as "with pelottes".
That was when I ordered it, the Skel Activator.
There are several activator with pellotes advertised now in the shop and they all have the plastic ball.

Yes it is a French word but why it appears in a German web site as a orthodontic term beats me.
French: from pelote ‘pelote’, ‘ball’,

Well German is a complicated language, and therefore I guess they where searching for an easy term to name that part of braces.
Does someone know, who actually invented them?