See also:

Winter tires
Do not drive with a tire tread depth of less than 0.16 in/4 mm. Below a tread depth of 0.16 in/4 mm, tires are less suitable for winter operation. ...

Exterior
The exterior remains the same for 2009, and the X3 retains its awkward angles, disjointed taillights and odd lower bodywork. It's not unattractive, but it sure isn't as stylish as Mercedes' new GL ...

Head airbags
In a lateral impact, the head airbag supports the head. ...