Shimano Di2 BTR2 Internal Battery Seat Tube Shim

Shimano Di2 BTR2 Internal Battery Seat Tube Shim. Shimano Di2 External Battery Mounts

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/