ROTOR BB386EVO 4624 Road Bottom Bracket with steel bearings and non-contact labyrinth seal. This ensures optimum protection against dust, water and dirt, while at the same time the best possible smooth running. Compatible with all ROTOR, Shimano and Shimano compatible cranks, with 24 mm axle. For road frames with the standard BB386EVO, a housing width of 86 mm and inner diameter of 46 mm.