Chevrolet 2006 Colorado Owner's Manual page 35

If the belt is not long enough, see Safety Belt
Extender on page 1-33.
Make sure the release button on the buckle is
positioned so you would be able to unbuckle the
safety belt quickly if you ever had to.
3. To make the lap part tight, pull up on the
shoulder part.
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
would 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.
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