Splined Bottom Bracket Designed For Use With Shimano Road Octalink CranksetOversize Bb Spindle - Large 22 Mm Diameter Chrome-Moly Hollow Pipe Billet Spindle Reduces Weight, Increases Strength And RigidityOctalink Splined Axle/crank Arm Interface - Results In A More Rigid Crank Assembly Compared To Square Tapered SpindleMaintenance-Free Sealed Cartridge Design Prevents Corrosion And Is Easy To InstallAluminium AdapterAverage Weight 250 G