Shimano Dura Ace 9100, big pulley and cage. Full ceramic bearings Specification. ■ Suitable for Shimano Dura Ace 9100 Big pulley cage. ■ Number of rotation; Chain drop and more. Expect a reduction enhance your efficiency reduces friction resistance and is powered from the effect of refraction angle. ■ pulley teeth number 12T (upper/16T (lower) ■ Max Low Gear Teeth 30T ■ pu-ri-bearinguhuruseramikku Ceramic (Ceramic Balls/bearings) ■ riadyire-ra-simano RD – R9100 ■ reference weight: G