Pontiac 2003 Aztek Owner's Manual page 38

To unlatch the belt, just push the button on the buckle.
If your vehicle has a bench seat, someone can sit in the
center position.
When you sit in the center seating position, you have a
lap safety belt, which has no retractor. You also
have a shoulder belt, which has a retractor. In order to
have the protection of the shoulder belt, you must
first connect it to the lap belt.
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