Shimano BT DN110 A7 Di2 Built-In Battery - North American Spec | Compatible with Road & Triathlon Bikes | Perfect for Long-Distance Cycling & Racing

Shimano Di2 Batteries. Must purchase battery, charger, and power cable to complete the system.

• 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/