This snazzy helmet will appeal to your 4 - 6 year old young cyclist with graphics that are out of this world!. The same great retention system found in bigger helmets--the Half Nelson(TM) system--provides an adjustable, solid fit. Cam-Lock(TM) retention system with 1/2" straps, and Pinch Guard(TM) buckle for a hassle-free, no pinch fit. Eight ventilation ports help keep them cool and ventilated. Nylon fit pads in multiple sizes provide a custom fit.