Children who have outgrown a harness car seat need to ride in a booster seat, regardless of their age, until they fit properly into the seat belt only. Seat belt should fit as follows:
- lap belt low (touching the thighs)
- shoulder belt across middle of chest and shoulder (not under arm or behind back)
- knees bent comfortably without slouching.
If your child does not pass this “fit test”, they need a booster seat!