Cadillac 2010 STS - Manual (Page 58)

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/
retailer 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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