Shimano - Di2 EW-JC304 Junction (2nd Gen) - 4 Ports
Shimano SD300
Introduced with the Shimano EP800 series, the SD300 E-Tube components form the interface between compatible STePS parts and expand the functional range of future Di2 systems.
Shimano Di2 / E-Tube junction for the connection of 4 EW-SD300 wires. Fixing by plug connection