See also:

Closing
Replace the fuel filler cap and turn it clockwise. The fuel filler cap audibly engages. Close the fuel filler flap. If you drive with the fuel filler cap open, the reserve fuel warning lamp ...

Rim
This is the part of the wheel on which the tire is mounted. ...

Installing the ball coupling
WARNING If the vehicle/trailer combination is not secured, the trailer may come loose. As a result, you could cause an accident. Therefore, make sure that the ball coupling is secured with th ...