Chevrolet 1998 Prizm Owner's Manual page 46

The safety belt locks if there's a sudden stop or a
crash,
or if you pull
the belt
very
quickly
out of
the retractor.
A
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, just push the button on the buckle.
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