Buick 2010 Lucerne - Manual (Page 65)

Safety Belt Extender
If the vehicle's safety belt will fasten around you, you
should use it.
But if a safety belt is not long enough, your dealer will
order you an extender. When you go in to order it, take
the heaviest coat you will wear, so the extender will be
long enough for you. To help avoid personal injury, do
not let someone else use it, and use it only for the seat
it is made to fit. The extender has been designed for
adults. Never use it for securing child seats. To wear it,
attach it to the regular safety belt. For more information,
see the instruction sheet that comes with the extender.
Child Restraints
Older Children
Older children who have outgrown booster seats should
wear the vehicle's safety belts.
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