The uniquely shaped hub provides the wheel with flex in the turns for grip and rigid support for speed The technology of the TORUS is initiated as your feet and body enter a turn. As your weight gets shifted to the outer edges of the wheel, the TORUS bends and deflects with you to keep you up and skating at extremely sharp angles. You will not slip out. This is due to 1) the flexible sidewalls of the TORUS; and 2) the hollow design of the TORUS which allows for room to flex. The Integrated Structure Ring (ISR) built into the TORUS is a stiff and rigid support ring. As you are in your stride you are skating on what is called the ''running surface'' of the wheel. The ISR prevents the wheel from deflection, which creates structure and integrity within the wheel and allows for Speed. TORUS features hollow cavities making the Variant wheel one of the lightest wheels on the market. RV-Urethane Wheel Compound This revolutionary urethane combined with the functionality of the TORUS has been tested to create 30% more grip than other brands.