Chevrolet 1993 Astro Passenger Owner's Manual page 41

The safety belt locks if there's a sudden stop or a crash.
CAUTION
You can be seriously hurt if your shoulder belt is too loose. In a
The shoulder belt should
fit
against your body.
b
crash you would move forward too much, which could increase injury.
To unlatch the belt, just
push
the button on
the
buckle.
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