Buick PARKAVENUE 1994 Manual page 30

The lap part of the belt should be worn low and snug on
the hips, just touching the thighs. In a crash, this applies
force to the strong pelvic bones. And you'd be less
likely to slide under the lap belt. If you slid under it, the
belt would apply force at your abdomen. This could
cause serious or even fatal injuries. 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's a sudden stop
or crash.
Shoulder Belt Height Adjuster
You can move the shoulder belt adjuster to the height
that is right for you.
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