KASK Protone is a lightweight road cycling helmet designed for performance riding, racing and fast training. It uses KASK’s Octo Fit retention system with rear dial adjustment, a low-profile road shape, and a well-ventilated shell aimed at balancing aerodynamics and airflow. The helmet has a removable, washable inner lining and a faux-leather chinstrap for comfort. This is the original Protone model, later replaced by the Protone Icon.