The BB52B Deore Outboard Hollowtech 2 MTB Bottom Bracket from Shimano is a genuine Shimano HollowTech II bottom bracket assembly. The set includes left and right hand cups, spacers, inner cover, and inner O-rings. The cups are sealed to help keep out dirt and water for a longer life span. It has ben designed for easy installation and maintenance free. Compatible with 68 and 73mm bb shells, comes in a durable Silver anodised finish only.