The Graco? Smart Seat? All-in-One car seat is the ultimate in car seat longevity. This convertible car seat fits your child from 5-100 lbs & features a convenient stay-in-car base so you only have to install the base one time! For your child's safety, the Smart Seat? has been side impact tested & SafeSeat Engineered. Both the car seat & the car seat base are steel-reinforced for strength and durability. For parent's ease of use, there is a one-hand height adjustable head rest with no-thread harness as well as an on-the-go recline so you can recline your child without having to re-install the seat. NHTSA has recognized Graco?s Smart Seat with the highest government rating for Ease of Use in all Modes. All car seats rated by NHTSA meet Federal Safety Standards & strict crash performance standards. While all rated seats are safe, they do differ in their ease of use in four basic categories: evaluation of instructions, vehicle installation features, evaluation of labels, and securing the child. Smart Seat received a five star rating in this evaluation.