Double-sided adapter nut: Allows direct threading into various bottom bracket cartridges
M8 threaded rod: Ensures compatibility with most bottom bracket tools and sockets
M12 and M15 threads: Enables use with Park Tool nine aluminum bottom bracket tools
Prevents cross-threading: Reduces risk of damaging bottom bracket components
Summarized by Shop
Bottom brackets have some of the highest torque specs of any component found on a bicycle. Despite this, some bottom bracket cups feature tool fittings that allow mere millimeters of engagement, which can be a problem when attempting removal or installation. Solution: the Park Tool Bottom Bracket Tool Retaining System. Used in conjunction