The Diono Monterey 4DXT Booster car seat, was remodeled and improved to provide upgraded practical features. It offers a contoured structure, that will easily adjust in height and width with one hand, to sportively protect your child as they grow from 40-120 lbs. In addition, the side panels of this booster enable free air flow, and contributes 3 layers of side impact protective features, to minimize pressure of abrupt stops. With just a simple click, easily transition this booster into a backless seat with a compact structure. Two side cup compartments allow your child to have their favorite drinks within reach as they enjoy the ride.