BM-DN100

Brand: Shimano

Mount for the external SM-BTR1 battery, screwed to the frame's bottle-cage bosses. It is the mount, not the battery, that carries the electronics: master unit, firmware updates through E-TUBE PROJECT and one E-Tube SD50 port. It is therefore what brings Synchro Shift to an external-battery build. Three versions exist: short BM-DN100-S (external or internal routing), long BM-DN100-L (external) and long BM-DN100-I (internal).