Shimano SM BTC1 Di2 Bottle Cage Battery Mount

We love the sharp, corrective shifting of Shimano's Di2 groups, but all that tech goes to waste without a power source. Enter the SM BTC1 Di2 Bottle Cage Battery Mount or rather, insert a BTR 2 battery into this thing and let the shift levers fly. The SM BTC1 mounts on your frame's water bottle cage bosses, where it serves as a Junction B in the Di2 system. It's got six E Tube wiring ports, and it keeps things tidy with internal wire organization and routing.