Shoei RF-SR - Streamlined Function. Equipped with many of SHOEI's top features while keeping functionality efficient and to the point, the RF-SR is anything but "entry level". Aerodynamic Shell Design: Aerodynamic properties are maximized through extensive wind tunnel testing and professional riders' feedback. Dual-layer multi-density EPS liner enhances impact absorption and ventilation. Four shell and EPS liner sizes present increased fit options that help to comfortably fit most head sizes. Ventilation System: Two upper air intake vents are positioned to maximize air volume into the helmet interior; hot air is exhausted through top outlet for a more comfortable ride. Lower intake vent absorbs air exhaled from the mouth to help eliminate shield fogging. Breath guard and chin curtain included.