Shimano BM-DN100 Battery MountThe BM-DN100 Battery Mount is ideal for use on frames that are running Shimano Di2 components externally. This mount is specifically designed for the new Bluetooth SM-BTR1 battery, which gives earlier versions of Di2 the feature of being able to change your shifting preferences wirelessly.Features: Former Di2 generations go wireless with this new mount External mount holds new wireless Bluetooth Di2 battery E-tube technology allows you to change your shifting preferences mid-rideA 2 year warranty is offered with all Shimano products from Chain Reaction Cycles (3 years on Dura-Ace and XTR products).Buy Shimano Components from Chain Reaction Cycles, the World's Largest Online Bike Store.