SUNCORD Magnetic Rear Derailleur Chain Supporter for Brompton Bicycle G Line

For use with integrated external bottom brackets (BB) 
Ring thickness: 2 mm >> Adjustable travel: 26 mm 
Comes with 3 selectable carbon plate lengths 
Compatible with 44T to 58T round chainrings (not suitable for oval chainrings).

Applicable Models: Brompton, Birdy, and other vertically folding bicycles.

Installation Notes:

• The magnetic pulley must be within 4 mm — it must not touch the chain.

• The distance cannot be too far, otherwise there will be a risk of chain drop.

Working Principle:
When the bike is folded, the chain is automatically attracted by the magnet and held in place, keeping it engaged with the chainring teeth and preventing slipping.
This naturally creates an anti-drop function for the chainring.
When the frame is unfolded, the chain automatically detaches from the magnetic pulley.
For best performance, it is recommended to use together with the Magnetic Rear Derailleur Chain Supporter.