The shimano deore sm bb52 outboard bearing bottom bracket set uses genuine shimano hollowtech ii bottom bracket assembly the set includes left and right hand cups spacers inner cover and inner o rings sealed cups keep out dirt and water this bottom bracket spare is maintenance free and is compatible with 68 mm and 73 mm shell it come with a durable anodised finish and the installation is simple and easy shimano deore sm bb52 outboard bearing bottom bracket set features genuine shimano