Gear sensor from Gearsensor.com
The original and in our opinion the best gear sensor from the clever guys in the Czech Republic.
Automatically cuts power from the motor momentarily when gears are shifted.
Suitable for both derailleur and Internal Gear Hubs.
Can be connected either to a brake input (with splitter cable if required), or ideally to the direct gear sensor input cable fitted to newer models of the BBS motor range.
See gearsensor.com for further details.