Fully aero to fully vented, the Kask Infinity Helmet allows you to switch the helmet vents from fully closed for maximum aerodynamics, to fully open for ventilation on hot days. The vents are quickly and easily opened or closed by adjusting the mobile aerator at the top of the helmet and can be partially opened to deliver a regulated amount of ventilation. The rounded profile minimizes interruptions to the airflow, and CoolMax padding provides moisture wicking and dries quickly. Multi-layer open-cell foam reduces head-to-pad contact by 70% to further reduce hot spots. The eco leather chin strap prevents allergies and irritation of the skin, while the internal strengthening frame prevents from secondary impact and makes the Infinity helmet one of the safest helmets of its category. 260 g. MD (48-58cm) or LG (59-62cm).