TEETH 60T CRANKARMS 170mm BCD 130mm Not include Bottom Bracket Pedal Size 916 Chain Size Standard 12 X 18 170mm crank arm length without any overlap of crank arm and chainring bolt Material aluminum alloy 7075T6 Burly and lightweight forged crankset for ultimate strength and reliability FIT for Single Speed Bikes Track Road Bike FixedGear Bike etc