The Shimano Dura-Ace FC-R9200 crank performs two vital functions; transferring your pedaling effort into the drivetrain and ensuring the fastest, most precise front shifting available. With HOLLOWTECH II crank arms to ensure light weight and Shimano's class-leading chainring designs, the FC-R9200 won't let you down.Optimal balance of stiffness, strength, weight and rotational performanceHOLLOWGLIDE structure cuts weight yet maintains strength for better power transfer and quicker, more precise front shifting