The Shimano 105 FC-RS510 crankset features a 2-piece design and is compatible with modern disc brake road frames. SPECS: Number of Chainrings: Double Color: Black Crank Length (mm): 172.5 Pedal Spindle: 9/16" Crank Intended Use: Road Chainline/Hub Compatibility: 135/142 Road Disc Hubs < 415 mm Chainstay Rings: 50/34 Spindle Interface Type: Shimano Hollowtech II Drivetrain Speeds: 11 Chainring BCD: 110 Shimano Asymmetric BB Included: No Chainline: 43.5