We feel that it's never too early to set a good example, especially when it comes to safety. At Joovy, we believe teaching children early about safety and creating good safety habits is an essential part of parenting. That's exactly why we developed the Noodle helmet. The Noodle helmet is for children with a head size between 18.5-20.5" (47-52 cm)(Small Helmet) and 20.5-22 (52-56 cm)(Medium Helmet) . We recommend using it when children ride bikes, trikes, ride-on cars, scooters, bike trailers and other activities like these. The Joovy Noodle features 14 air vents, with integrated bug mesh in the front vents, extended visor for maximum protection, nylon straps, pinch guard chin strap, and an adjustable fit dial. It is a great looking helmet and comes in various colors. Meets CPSC Standards.