Having the right tool for the job is essential for any home mechanic or bike shop. This high quality investment cast steel bottom bracket tool from Ashima will get the job done. The 16 notches are compatible with external bearing bottom bracket cups like Shimano's Hollowtech II, and Campagnolo Ultra and Power Torque. The 1/2 inch driver on the back also means you can use it with a torque wrench or any other 1/2 inch socket driver. Also compatible with external bearing cups from Race Face, FSA, Truvativ and others.