Shimano m810 saint hollowtech ii bottom bracket features genuine shimano hollowtech ii bottom bracket assembly length of screw thread is increased to enable the fitment of chain devices set includes left and right hand cups spacers inner cover and inner o rings light weight seal structure helps to remove vital grams sealed cups keep out dirt and water maintenance free compatible with 68mm and 73mm shell 68 and 83mm shell 83 durable gold anodised finish