SHIMANO - Di2 Battery - BT-DN300

With the same size as the previous model, the slim DN300 battery can be housed inside the seatpost or frame for a cleaner look. Now equipped with 3 ports, the DN300 battery simplifies wiring of the front and rear derailleurs and provides stable power at all times. The third port is intended for cyclists who want to keep the Shimano Di2 12-speed wired option.