Shimano BB-MT501 Hollowtech II English Bottom Bracket Description: The Shimano BB-MT501 Hollowtech II Bottom Bracket features sealed bearing to keep contaminants out for increased bearing life. Features: Fits Shimano Hollowtech II Cranksets For use with mountain cranks Aluminum threaded cups Replaces SM-BB52 model Specifications: Frame Interface: BSA/English Threaded Spindle Interface: 24mm (Shimano Hollowtech II, FSA MegaExo, Surly OD, FSA MegaExo Light, RaceFace EXI) Bottom Bracket Shell ID: 1.37 Shell Width: 68mm, 73mm Color: Black Weight: 95g