The Go Hybrid? Booster Car Seat installs in less than a minute, making this car seat ideal for parents and children on the go! The seat starts out as a high back booster and will keep your child secure in a 5-point harness all the way up to 65 pounds. As your child gets ready to transition over to the adult seatbelt, the Go Hybrid? Booster Car Seat converts to a backless booster that can accommodate your child all the way up to 100 pounds!