To clean the lid you have to turn the white interior via a resistor and can also be removed from the lid it then. Inside is a rubber trim attached that, if you do not regularly clean, dirty quickly and disgusting. Eventually I even moved out of sheer frustration his little finger into the rubber lining and behold, so you get them perfectly clean. When rinsing so no problem.
Overall, in my view, stable and therefore good Sigg Quality: 5 Stars.