SRAM Force 1 Crankset - 170mm 10/11-Speed 50t 110 BCD GXP SpindleCarbon fiber arms with structural foam core provide excellent strength to weight. Tall teeth with alternating narrow and wide profiles retain chain over rough terrain. Hidden" chainring bolt threads into crank arm to enhance chainring stiffness Q factor is 145mm Product Specifics Drivetrain Speeds: 11 Drivetrain Speeds: 10 Rings: 50 Defined Color: Black Spindle Interface Type: TruVativ GXP Spindle Interface Type: SRAM Truvativ GXP Number of