Shimano BB-MT501 outboard bearing bottom bracket set, English thread, 68 / 73 mm Genuine Shimano HollowTech II bottom bracket assembly Set includes left and right hand cups, spacers, inner cover, and inner O-rings Sealed cups keep out dirt and water Maintenance free Compatible with 68 mm and 73 mm shell Durable anodised finish Easy installation Any questions please feel free to contact us. Please check out our other listings