Oh, you know I did remember seeing one of those on AGT. It didn't quite look the same and the man playing it didn't quite have the skill level-Google it. It just occurred to me! I thought the guy invented it, the music was a little strange. This music Somewhere Over the Rainbow was beautiful.
The bandoneón is a kind of concertina used for playing Argentine tango music. The instruments were mass produced by a German company until World War II, but nowadays only a few luthiers make them by hand. As a result, they are fairly rare and expensive.