Brand New XD4 Arai did the only thing possible to this groundbreaking, critically acclaimed street and dirt crossover helmet. We made it even better. Intermediate-round oval shape: The new XD4 has Arai's intermediate oval (IO) interior shape. New exhaust ports and shell shape: These new top-diffuser-vent ports nearly double the XD4's airflow, while its new shell shape provides better aerodynamic stability at higher street speeds in concert with its high-flow peak and new side cowl vents. New larger side cowl vents: The new larger, sculpted vents improve ventilation efficiency as well as helmet stability on your head at speed. New chin vent: The new vent has more intake ports for improved airflow. And like its predecessor, the vent's chin bar is rounded with less protrusion making it less likely to catch and dig in during a spill, than most other designs. Its oval form is actually based on the egg's, long known for its extremely strong and efficient shape. FCS cheek pad system: Arai's amazing new patent-pending FCS (Facial Contour Support) cheek pad design delivers comfort, support and fit like nothing you've ever felt, and it features our exclusive 5 mm peel-away custom fit layer. New brow vent face shield: Arai has added our trademark brow vents to the new XD4 face shield, providing airflow to the temple area of the head. Fully removable/replaceable/washable interior: Includes Arai's patented Dry-Cool technology to keep you drier and cooler (hence the name) for greater long-haul comfort. Emergency cheek pad release system: From Arai's decades long commitment to building helmets that do more for riders comes this major innovation, the very first emergency release cheek pad design created specifically for motorcycle helmets. Developed to allow easier access to an injured rider, the XD4's cheek pads slide out easily via the integrated pull-tabs built into the underside of the cheek pad, making helmet removal much easier for trained medical personnel.