Shimano brings Synchro Shifting to current Ultegra 6870 and Dura-Ace 9070 groups - BikeRadar
Di2 vs eTap: which is the right electronic groupset for you? | Cyclingnews
Shimano Makes Electronic Shifting More Affordable With Deore XT Di2, Offers More Drop Bar Configurations and Bluetooth Connectivity - Cyclocross Magazine - Cyclocross and Gravel News, Races, Bikes, Media
Technical FAQ: Using Di2 Synchro Shift - VeloNews.com