The Marathon is a Convertible Child Seat with LATCH, the system for simple and secure installation in any car. Its Five-Point Polyester Harness with strong no-tangle polyester webbing fits snugly over the child's shoulders, collarbone and hips. It's adjustable to provide a more secure fit as your child grows, and is more secure than any other harness or strap type. Its impact absorbing EPS foam insert increases available shoulder width room -- already the largest in its class -- by 1.5 inches. The innovative patented "Floating" HUGS System is designed to better distribute webbing loads to reduce head movement, minimize the chance for webbing edge loading on the child's neck in the case of an impact, and reduce the chance of improper positioning of the chest clip. Four different shoulder harness positions will accommodate the taller child, and the newly designed base facilitates a secure fit in most autos.