See also:

Bead
The tire bead ensures that the tire sits securely on the wheel. There are several steel wires in the bead to prevent the tire from coming loose from the wheel rim. ...

Left control panel
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Nuts & Bolts
Overall reliability for the current C-Class has been average. In crash tests by the Insurance Institute for Highway Safety, the car earned the top score of Good in front, side, rear and roof-crush ...