A precision CNC-machined aluminum tool for the installation and removal of select threaded bottom brackets with 16-notch tool fittings including Shimano® Ultegra® BBR60 and Deore XT® MT-800 bottom brackets. Manufactured in-house by Park Tool anodized for easy identification and featuring a ratchet/torque wrench-compatible 3/8' drive. The BBT-59.3 features integrated threads for full compatibility with the Park Tool BBT-RS Bottom Bracket Tool Retaining System sold separately. The BBT-RS uses an adjustable spring-based tension system to apply consistent adjustable pressure to the tool ensuring full engagement with the tool fitting and preventing slippage. BBT-59.3 FEATURES Fits 16-notch threaded bottom bracket tool fittings with a major diameter outside of notches of 41–42 mm and a minor diameter inside of notches of 39 mm including: Shimano® Ultegra® BBR60 Shimano® Deore XT® MT-800 3/8' drive fitting