The Shimano Deore Hollow Tech Bottom Bracket is a Genuine Shimano HollowTech II bottom bracket assembly which includes left and right hand cups, spacers, inner cover, and inner O-rings. Shimano Deore Hollow Tech Bottom Bracket Features 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 83 mm shells Durable anodised finish Easy installation