See also:

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. ...

Windows fogged up on the outside
Switch on the windshield wipers. Activate automatic climate control. You should only select this setting until the windshield is clear again. ...

Optional Features
A number of packages and individual options are available for the GLK350. The Premium Package bundles a number of features, including a panoramic moonroof, power liftgate, a memory feature, Sirius ...