See also:

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. ...

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. ...

General notes
USA only: This device complies with Part 15 of the FCC Rules. Operation is subject to the following two conditions: 1. This device may not cause harmful interference, and 2. this device must ...