TheShimano Deore XT M8100 12 Speed Double Front Derailleuris alightweight front mount 12-speed double MTB derailleur for smooth gear changes. Designed specifically with modern trail bikes in mind, Shimano Deore XT side swing technology front derailleurs increases tyre clearance by 15mm, while new cable routing results in the lightest shifting action yet. Shimano Deore XT M8100 12 Speed Double Front DerailleurFeatures Designed specifically with modern trail bikes in mind, Shimano XT side swing technology front derailleurs increases tyre clearance by 15mm, while new cable routing resulting in the lightest shifting action yet Side pull cable routing Reinforced light weight chain guide adds rigidity and improved response Wider pivot link increases torsional rigidity Easy access angled adjustment screws and clamp bolt Angled inner chain guide tail for increased tyre clearance For use with 12-speed MTB drivetrains Specifically developed for 68 and 73 mm bottom bracket shells, with a 48.8 mm or 51.8 mm chain line 66-69 degree chainstay to seat tube angle range 36-38 tooth outer ring compatible