A travel system is a standard stroller and a compatible infant car seat that clips into the stroller. Seats in infant travel systems recline all the way to securely hold the baby in the car seat. When your baby is big enough, and he/she can sit in the stroller alone without a car seat. A travel system may not be necessary if you already have a full-size stroller, or you have a universal car-seat carrier. Choose from many different designs and brands to fit your style. Popular picks are Chicco Cortina SE KeyFit and Graco Stylus - FREE SHIPPING on all travel Systems.