Shimano Di2 BT-DN300 Battery Built-In for SD300 Wires

All Di2 components on the bicycle require the same firmware version. Using Di2 components with different firmware versions may cause malfunctions
Use Di2 system checker to update component firmware from http://e-tubeproject.shimano.com/
Compatible with thinner, next generation electric SD300 wires and R9150 and R8150 series systems
Features three SD300 wire ports
Shared fixing method with BT-DN110
Built-in type
U.S. spec
Charger and power cable sold separately