Brompton gear indicator chain for 5 speed blue Sturmey (post 1999)

If you have a 5 speed Sturmey Archer hub gear on your Brompton and need to replace the indicator / gear change chain - then it's best to clean it and check the end (see picture).

It will be marked blue (this one) or red.

You can also check on the hub itself - where Sturmey Archer will have stamped the manufacture date - just to double check. 

Brompton reference: QGICH5B