This helmet combines light weight of 6.6 oz (186 g) (S/M) and protective performance to protect the head. Kevlar and carbon inserts between shell and foam for superior protection Many large ventilators from both sides to back provide excellent breathability and reduced weight. The large ventilation opening is specially designed for rock climbing which is less likely to fall off. Not suitable for climbing or ice climbing. [Features] Polycarbonate shell and EPS foam co-molded A large ventilator with excellent breathability. Adjustable size by ratchet adjuster. Removable headlamp clip Line up of 2 sizes.