The shimano mtb press fit 42mm bottom bracket has cups that are made from a fibre reinforced polymer material which reduces the risk of frame noise and damage this complete xtr level press fit bottom bracket has sealed cups to keep out dirt and water and to give it a longer life span the bottom bracket will require no maintenance and has an easy press fit installation itrsquos compatible with 92mm shells or 895mm shells with a 25mm spacer this set includes left and right hand cups 25mm