Park Tool BBT-147-12 Steel Bottom Bracket Tool Description: The Park Tool BBT-147-12 Steel Bottom Bracket Tool is a rugged, shop-quality tool specifically designed for the installation and removal of select bottom brackets with 12-notch tool fittings. Precisely machined 4140 tool steel ensures long life, and a 3/8" ratchet, a 1" hex fitting, and 36mm wrench flats give plenty of options for applying the leverage needed to remove the most stubborn components. Note: This tool is not rated for use with impact tools/drivers. Features: Constructed from precision-machined 4140 steel the BBT-147-12 is a heavy-duty tool for the removal and installation of select bicycle components with a 12-notch tool fitting Features an extra deep body to accommodate extra wide spindles and low profile walls at the point of engagement for recessed lockrings Fits 12-notch threaded bottom bracket tool fittings with a major diameter (outside of notches) of 50-53mm and a minor diameter (inside of notches) of 48.2mm Three methods of tool engagement include a 3/8" drive fitting, a 1" hex fitting, and 36mm wrench flats Can be used to install/remove (among others): BBInfinite T47 Chris King ThreadFit 30 Chris King ThreadFit T47 Chris King ThreadFit T47 24x Chris King ThreadFit T47 30 Hambini T47 Rotor T47 External 30mm Rotor BBright BB30 BB386EVO PF30 thread-together