The Shimano Deore 12-speed crank features a new construction, using direct mount chainrings and a unique gear tooth profile for improved chain retention. The Deore crankset is available in the M6100, M6120, and M6130 models. Details: Model No: FC-M6100-1, FC-M6120-1, FC-M6130-1 Series: Deore M6100 Chainring combination: 30t, 32t Crank fixing bolt included Gear arms: 4 P.C.D: Direct Rear speeds: 12 Chainring included: Yes Compatibility: The Shimano Deore 12-speed crank arms are compatible with the following: Chain: Shimano HG 12-speed Chainring: Shimano direct mount chainrings: M6100 Bottom Bracket: Shimano Hollowtech II bottom brackets