Autofit® System - a self-adjusting harness that is easy to use for both children and parents. It ensures that the helmet fits securely and snugly on your child's head thanks to the cushioned, self-adjusting design. Just place the helmet on your child's head and the retention belt will automatically attach so that the helmet fits perfectly. It uses consistent spring tension to hold the helmet securely in place. The reverse progressive spring ensures that the harness tightens with the same gentle pressure regardless of the size of the child's head. This means that the helmet adjusts for a perfect fit every time you ride. No need to adjust the straps every few weeks, Lazer's AutoFit® system keeps up with even the smallest changes from ride to ride.