Whether in a bike trailer or on a LikeaBike, even the littlest ones ride in style. The Action Fit System allows for easy adjustment of the helmet to fit the shape of the head, and the side closure can be easily managed even on excited little ones. Sizes: T: Head circumference 45-52cm C: Head circumference 48-55cm Colors: black with checkerboard, green with mini-monster, blue with clownfish