What do I need to use Synchronized Shifting?
Synchronized Shifting is available to everyone running current or previous generation Di2 with up-to-date firmware and the BT-DN110 battery or BM-DN100 external battery mount installed.
The synchronized-shifting compatible series are:
Ultegra 6870 Ultegra R8050 DURA-ACE R9000 DURA-ACE R915 Synchronized Shifting is also available on mountain bikes. In order to use synchronized shifting on a mountain bike you need up-to-date firmware, the BT-DN110 battery or BM-DN100 external battery mount and also a System Information Display (SC-M9050, SC-M9051 or SC-MT800).
The synchronized-shifting compatible mountain series are:
XTR M9050 Deore XT M8050