Patented carbon-fiber tensile cords and loaded high-temperature rubber provide exceptional belt stability and excellent sidewall friction characteristics.Carbon-fiber tensile cords are 25-30% stronger than cords, providing ehorsepower and drive-torque handling capability for 800cc and larger engines.Carbon fibers stretch 60% less than fibers at the same load conditions, enabling faster acceleration and more consistent CVT shift performance.Trapezoidal top-notch and rounded bottom-cog belt designs increase belt flexibility and cooling, with smooth pulley intake and out-feed for smoother overall CVT operation.Patented designs and materials create a belt with outstanding operating life with dramatically reduce sidewall cord pull-out.C12 Carbon-fiber CVT Drive belts deliver exceptional performance for the most demanding recreational, trail, off-road and competitive machines and their riders. Developed by the leader in belt innovation and technology, C12 belts are the first in the industry