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. ...

Internet
Further information about Mercedes-Benz vehicles and about Daimler AG can be found on the following websites: http://www.mbusa.com (USA only) http://www.mercedes-benz.ca (Canada only) ...

Removing the mechanical key
Removing the mechanical key Push release catch 1 in the direction of the arrow and at the same time, remove mechanical key 2 from the SmartKey. ...