Park Tool BBT-49.3 Bottom Bracket Tool Description: The Park Tool BBT-49.3 is a bottom bracket tool for the installation and removal of 16 notch bottom brackets. Features: Fits 16-notch threaded bottom bracket tool fittings with a major diameter (outside of notches) of 39-40 mm and a minor diameter (inside of notches) of 37.6 mm Fits Shimano XTR BB93, Dura-Ace BB9000, and Token Featuring a ratchet/torque wrench-compatible 3/8" drive