The BBT-9 is used to remove and install external bearing crankset bottom brackets. One end of the BBT-9 securely engages the 16 notches of the bottom bracket cups. The other end of the tool engages the 8 internal splines of the crank arm adjustment cap. The BBT-9 fits cups and lockrings with 16 external notches and an outside diameter of approximately 44mm. The BBT-9 works with many external bearing crankset bottom brackets, including: Shimano® Hollowtech II Campagnolo® Ulta-Torque and Power Torque Race Face® FSA® SRAM® Truvativ® Chris King® Phil Wood® outboard bearing The BBT-9 also fits rotor disc lockrings which use 16 external notches.