Shark back is the last evolution of back. It has shark vents on the side for cooling system. The shell is multilayer composite with fiberglass and carbon fiber. The base of the butt truck is integrated. General shape design allows a good mechanical stability to position of the spinning wheels. The independent inner soft shells allows and accompany motion freedom of the back spin, from arching, to bend forward. It has adjustable Y form elastic straps on the flanks to always keep chest in contact. It has a adjustable harness to string up the body during “luge” (sit) and “gognoc” position. Strap and wire sewings quality comes from paragliding technology (SUP AIR). Buckles from ITW Nexus used in US Army : safe, reliable, efficient, light. The 74 mm wheels has narrow profile to avoid wobble.