#1 Rated Infant Car Seat in America! The Chicco KeyFit Infant Car Seat is the premier infant carrier for safety, comfort, and convenience. With its removable newborn insert, the KeyFit Car Seat will accommodate your baby from 4 to 22 pounds. The KeyFit’s thickly cushioned seat includes a five-point safety harness and is lined with energy-absorbing foam for increased safety and comfort. The KeyFit Base’s spring-assisted level foot, two precision bubble levels, and “Center-Pull” LATCH adjustment guarantee quick and correct installment from either side of your vehicle and give you confidence that your child is safely secured in your vehicle.