The Shimano FC-M5100 crankset features an optimized gear combination and gear ratios designed for trail riding. SPECS: Number of Chainrings: Single Color: Black Crank Length: 170mm Chainline/Hub Compatibility: 141/148 Boost Hubs Pedal Spindle: 9/16" Crank Intended Use: Mountain Rings: 32t Spindle Interface Type: Shimano Hollowtech II Drivetrain Speeds: 10 , 11 Chainring BCD: 96 Shimano Asymmetric BB Included: No