Shimano BB-MT800 Press Fit Bottom Bracket Complete XT level press-fit bottom bracket assembly for Shimano HollowTech II MTB cranks Cups are made from fibre reinforced polymer material which reduces the risk of frame noise and damage Set includes left and right hand cups, 2.5 mm spacer, inner cover, and inner O-rings Sealed cups keep out dirt and water Maintenance free Compatible with 89.5 mm (with 2.5 mm spacer) and 92 mm shells 41 mm cup diameter Easy press-fit installation