Shimano SM-JC41 Di2 Internal Junction B Box Groupe thanks to the matching dimensions

thanks to the matching dimensions and complete compatibility with wheels and frames

Carbon fiber is the ideal material for a gravity bar because fiber orientation and bar shape can be controlled independently and developed in unison

One piece alloy body design

PRINT/INK: Black/Gloss

These lugs are shaped to allow a supple feel for pavement and hardpack surfaces

Shimano SM-JC41 Di2 Internal Junction B Box Groupe thanks to the matching dimensionsFor internal DI2 wire routing, SHIMANO's SM JC41 Junction B is the central connector for DI2 systems. Wires from the front and rear derailleurs, cockpit area, and battery all plug into the 4 port SM JC41 junction, which is housed inside the bike frame. Specifications For internal wire routing Mfr Claimed Weight 4. 1g