The latest in the Axis family yields a higher cut shell and removable liner. If you are looking for new technology, lightweight, and constant temperature maintenance, Axis Rage is it. Chimney vents draw hot air out of helmet, while heat generated by your body is absorbed into the 'Outlast' fibers, reducing overheating. Stored heat is released back to your body as needed, maintaining your own temperature regulated zone. All of these European helmets run a full size smaller than USA helmets, when ordering judge accordingly.