The new booster seat from chicco that follows the growth of your child could be used as a normal booster seat with back rest for 6m babies and the backrest is removable to be used from 36m retractable strap system permits to attach on the bottom and the back of the chair with a practical button which locks the straps when reaching the right lenght when detached the straps retract automatically just pressing a second button adjustable to 3 height position just by pressing the buttons on up