Hummer 2006 H3 - Manual (Page 29)

To unlatch the belt, just push the button on the buckle.
The belt should go back out of the way. When the
safety belt is not in use, slide the latch plate up
the safety belt webbing. The latch plate should rest
on the stitching on the safety belt, near the guide loop
on the side wall.
Before you close the door, be sure the belt is out of
the way. If you slam the door on it, you can damage
both the belt and your vehicle.
Shoulder Belt Height Adjustment
Before you begin to drive, move the shoulder belt height
adjuster to the height that is right for you.
Adjust the height so that the shoulder portion of the
belt is centered on your shoulder. The belt should
be away from your face and neck, but not falling off
your shoulder. Incorrect positioning of the shoulder belt
can reduce the effectiveness of the safety belt.
To move it up or down,
press the square button (A)
in the center of the
height adjuster knob and
move the height adjuster to
the desired position.
After you move the height adjuster to where you want
it, try to move it up and down without touching the
square button to make sure it has locked into position.
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