We purchased this booster seat for our son 3 months ago after much research and taking him for test drives in them...we just love it..it is fior children 40 lb to 120 lb (18.2 - 54.4 kg) and 38" to 63" (96.5 cm to 162.6 cm) in height...it has extra deep sides...has adjustable height and width...and a longer seat...these features were really important to us as our son is on the bigger side and has broad shoulders...also uses the UAS for secure installation...you don't have to use them but you can...converts to backless booster when your ready...dual cup holders...it is a little more expensive than some, but so worth the money...our 4 year old loves, and constantly tells us how comfy he is in it...the company also offers tons of accessories for traveling with the seat, or just for everyday in the vehicle....