3 sprockets (12-15-17) or (12-14-17)
Spacer and C clip
Custom made 9 spline Shmano spec, compatible with Stock Brompton 2 speed hub and most third party external cog wheel mods (e.g. MiniMODs, Orz ... )
Not compatible with Sturmey Archer SRF-5 (W) 5 speed hub, but compatible with SRF-5(N) 10 (5x2) speed hub, so 5x3 is possible ... see photo below. Note: The black spacer should be put in between 17t and 15t (or 14t), 12t has built in extrusion rim underneath, so no need to use spacer.
Titanium Barrel nut shifting cable terminal fixed.