7 Speed Rear Derailleur and Tensioner Set for Brompton Bicycle
For Brompton P/T Line or A/C/E Line (Adaptor Included)
By using with 10s cogs can support max 7 speed.
Due to Brompton frame design, the best result will be 5 speed.
Support up to 23T.
From our experience, 5 speed with 11-13-15-17-21 (9s cogs) with best performance.
6 speed with 11-13-15-17-19-21 (9s cogs).