Shimano Internal Battery Master Unit for your Shimano Di2 system. This battery weighs just 50g, and is mounted inside your seatpost.
- E-Tube Port
- Type: Built-in battery
- Battery: Li-Ion
- Rated Voltage (V): 7.4
- Rated Capacity (Ah): 0.5
- Rated Capacity (Wh): 3.7
- Compatible Charger: SM-BCR2
- Average Weight: 50g