The Child's Booster Cushion is to increase a child's height approximately 3". This is to enable the seat belt to ride at the appropriate level across the lap and diagonally across the collar bone below the neck. Severe injury can be caused when a seat belt does not fit a child or person adequately. Because many State laws only require children to be in a safety seat up to age 4 or so, many parents assume older kids are safe in just an adult safety belt. However, all children need to be restrained correctly whenever they ride in a motor vehicle - every trip, every time. New Ohio state law will mandate that seat belts fit all children adequately by April 15, 2010