The Leatt-Brace? is an injection produced glass reinforced nylon or carbon fiber and Kevlar neck brace system designed by medical professionals and motorcycle enthusiasts to help prevent: Hyperflexion: extreme forward head movement Hyperextension: extreme rearward head movement Lateral Hyperflexion: extreme sideways head movement Axial loading: compression of the spinal column due to the effect of force on the helmet Posterior hypertranslation: rearward movement of the head/helmet on the neck.