X4 Brompton 3rd party 2/3 speed Hub 4 speed External 4 Cogs upgrade kit (MiniMODs) X4 Brompton External 4 Cogs upgrade kit compatible with MiniMODs, Hubsmith 2/3 speed hubs and most ORZ rear hubs Options: (a) Circlip type kit :Circlip type 4 speed free hub body x 1.
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