Belt-positioning booster seats are designed to raise the child up and help to position the vehicle lap and shoulder belt correctly. When a child is properly positioned in a belt-positioning booster seat so that the vehicle restraint system can be used, the child’s risk of injury in all types of crashes is reduced. In the event of a crash, the vehicle seat belt system provides all of the crash protection for a child in a belt positioning booster seat. Because a seat belt extender modifies the existing vehicle seat belt system, it should be approved for use by the vehicle manufacturer prior to use with a booster seat.