The Hollow Tech II 10-speed CX50 cyclo-cross chainset is the perfect choice for enthusiast riders Alloy chainrings are both rigid & 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 & enhanced power transfer Industry leading cold forged crank arms have been evolved to increase rigidity reduce weight & improve strength 2-piece cap-free design is quickand easy to install whilst being lighter & stiffer than a traditional crank / bottom bracket assembly Integrated bottom bracket seal design has minimal bearing interface ensuring smooth rolling & increased durability 46 / 36T chainrings using 110 mm bolt circle diameter