This particular car seat is for babies at birth to 20 lbs. An infant seat is probably the safest for newborn babies because it is small enough to fit snug around and infant. Infant carriers with bases are more convenient and some say they are safer.Most infant carriers come with bases that can be installed separately. The base is left in the vehicle, and the carrier is easily installed or removed from the base without taking the baby out of the harness. An extra base can usually be purchased separately for another vehicle. The infant carriers can be installed in the car without the base, but a few models may require the base for installation so check to make sure.
Here are some steps to help ensure your infant is properly restrained in their infant-only rear-facing seat:
Place harness straps at or below infant's shoulders and make sure they are snug.
Place chest clip at your infant's armpit level to keep harness straps in place.
If necessary, place rolled towel around baby's head and neck for support.
Do not put heavy clothing or jacket on baby because it prevents harness straps from being snug and could cause baby to jerk forward during a crash.
Never place any extra cushioning under or behind your baby. This also prevents harness straps from being snug. If additional padding is needed, use only the padding that comes with your child safety seat.
Secure your infant in the seat and then place a blanket over him/her (do NOT cover infant's head).