Fisher-Price 79752 Guide De L'utilisateur page 19

Restraining Your Child
WARNING
USE ONLY the vehicle's lap and shoulder belt system when
restraining the child in this booster car seat. Using a lap only
belt only will still allow your child's head to move forward in
a sudden stop or crash, possibly causing your child's head to
strike the vehicle's interior or your child's knees hard enough
to cause injury or death.
17 Booster Car Seat