The choice of the pros. Precision and exceptional strength have led the Astana Qazaqstan Team to choose this series of four-hole chainrings with High Stiffness Points (HSP), compatible with the Shimano ® Dura-Ace FC-9200 12v crank set. Manufactured from CNC-machined AL 7075 T6 aluminium alloy with a black total anodizing surface treatment (TT). Five teeth options available for internal chainrings and six for external chainrings. Aluminium chainring bolts included.