karmor ditro Asian fit With JCF official seal Bicycle Road bike Helmet Purchased for just under 25,000 yen I believe the size is S/M My daughter, whose head circumference is 53cm, used it. It has an adjustment dial. Worn only once in a competition. There are some marks from the race number stickers from a triathlon competition (Please check the photos 2 and 7) I wiped it with a disinfectant wipe before listing it. Since there is no box, I will put it in a different box, the cannondale box in the photo, and wrap it in bubble wrap for shipping. Please understand the above points, and that this is a used item. Road bike Cross bike Mountain bike Triathlon Duathlon etc.