Description Shimano SM-MT501 HollowTech II Bottom Bracket Known for its reliability and cost-effectiveness, the SM-BB52 offers easy installation and maintenance, making it a popular choice. Genuine Shimano HollowTech II bottom bracket assembly Set includes left and right hand cup, inner cover, and inner O-rings as per photograph only Sealed cups keep out dirt and water Maintenance free Compatible with 68 mm and 73 mm shell Durable anodised finish Easy installation Brand new condition