Hummer H2 2009 Owner's Manual page 67

4. Pull the rest of the shoulder belt all the way out of 5. To tighten the belt, push down on the child restraint,
the retractor to set the lock. pull the shoulder portion of the belt to tighten the lap
portion of the belt and feed the shoulder belt back
into the retractor. When installing a forward-facing
child restraint, it may be helpful to use your knee
to push down on the child restraint as you tighten
the belt.
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