Chevrolet 2006 Avalanche Owner's Manual page 33

CAUTION:
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You can be seriously hurt if your shoulder belt
is too loose. In a crash, you would move
forward too much, which could increase injury.
The shoulder belt should fit against your body.
To unlatch the belt, push the button on the buckle.
Rear Safety Belt Comfort Guides
Rear shoulder belt comfort guides may provide added
safety belt comfort for older children who have outgrown
booster seats and for some adults. When installed on
a shoulder belt, the comfort guide positions the belt
away from the neck and head.
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