See also:

Snow chains
For safety reasons, Mercedes-Benz recommends that you only use snow chains which have been specially approved for your vehicle by Mercedes-Benz, or are of a corresponding standard of quality. ...

Activation conditions
You can activate the HOLD function if: Rthe vehicle is stationary. Rthe engine is running. Rthe driver's door is closed or if your seat belt is fastened. Rthe electric parking brake is released. ...

Treadwear indicators
Narrow bars (tread wear bars) that are distributed over the tire tread. If the tire tread is level with the bars, the wear limit of 1/16 in (1.6 mm) has been reached. ...