See also:

General notes
WARNING If the vehicle becomes trapped in snow, ensure that snow is kept away from the exhaust pipe and from around the vehicle as long as the engine is running. Otherwise, poisonous carbon ...

Mercedes-Benz M-Class Owners Manual
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Emergency Tensioning Devices, beltforce limiters
The seat belts for the front seats are equipped with ETDs/belt buckle tensioners and seat belt force limiters. The outer seat belts in the second row of seats are equipped with ETDs and seat belt f ...