The hollowtech ii 10 speed cx50 cyclo cross chainset is the perfect choice for enthusiast riders alloy chainrings are both rigid and lightweight the chainring teeth have been developed to work in conjunction with the 10 speed directional hg road chains for increased contact to provide greater efficiency and improved power transfer industry leading cold forged crank arms have been evolved to increase rigidity reduce weight and improve strength 2 piece cap free design is quickand easy