i believe 4,5
To get out a booster seat you have to be at least 4 feet 9 inches
No more than 2 to 2-1/2 feet tall
It is not "age" that determines this ... more so "height" and "weight". State laws differ, but there are minimal height requirements for children using the regular seat belts in auto's and trucks.
Not until the seat belt will fit properly without use of a booster seat.
you have to be 136cm or over
It depends, as they need to fit the weight and height requirements specified in your vehicle manual, to sit in a seat unassisted. Unless there is a local bylaw requiring people of a certain age, height or weight either to sit in a booster seat, or not in a booster seat.
When they are around 2 and have outgrown their child seat. They should continue to use a booster seat until they reach the height of 4 foot 9.
135
The AAP instructs to go by height, not weight now (2010) -- a minimum height for a child's no longer needing a booster seat is four feet, nine inches. 4'9."
I do believe you have to be eight years old or 4 feet.
When they about the height of 4'9".
A company by the name of graco makes great booster seat products for children. Again this isn't the only company that makes a great booster seat but their chairs are dependable and safe.