The thing about the Schraubknubbel might sound a bit uncomfortable at, but it is not. On the contrary, no more pressing in the ear canal, no wobbling and no constant concentration on the earphones that could possibly fall out. And since everything is made of soft plastic, pressed and scrubs nothing, but is soft to the touch.
For the actual earphones, there is an adapter for larger ears and foam covers. Three different sized adapters are for Fixierknubbel. The whole can then still stuck in a shiny case.
The sound is excellent for earphones in this price range: clear midrange and treble, clean bass - Sennheiser precisely.
For those with problem ears these earbuds are highly recommended.