"DURA-ACE FC-R9200 crank, the heart of the bicycle, ensures that no portion of your pedal stroke is wasted. With hollow arms and chainrings, weight is kept to a minimum but stiffness and shifting precision is maximized. The 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. The FC-R9200 is offered in even shorter crank arms lengths to offer fit options for any rider. FEATURES Optimal balance of stiffness, strength, weight and rotational performance HOLLOWGLIDE structure cuts weight yet maintains strength for better power transfer and quicker, more precise front shifting New 54-40T option to realize the most efficient drivetrain"