Cadillac 2007 CTS Owner's Manual page 37

The shoulder belt should go over the shoulder
and across the chest. These parts of the body
are best able to take belt restraining forces.
The safety belt locks if there is a sudden stop or
a crash, or if you pull the belt very quickly out
of the retractor.
CAUTION:
{
You can be seriously hurt if your shoulder
belt is too loose. In a crash, you would
move forward too much, which could
increase injury. The shoulder belt should
fit against your body.
To unlatch the belt, push the button on the buckle.
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