The 5 point harness ensures a snug and secure tangle free fit, while the LATCH connectors provide easy and tight installation. The Versa-Tether anchors the top of the seat to the vehicle to reduce movement in the event of an impact, and also provides stabalization when used as a rear facing seat. The Marathon is designed to hold a 5 to 35 pound child sitting 9.5" to 16" high at the shoulder in its rear facing position. For forward facing, it is designed for a 20 to 65 pound one year old child sitting 12" to 16" at the shoulder. The Britax Marathon is available in a wide array of fabric fashions, and is also certified for aircraft travel.