Shimano Dura-Ace/Ultegra Di2 SM-JC40 External Wire Junction Box

Junction box for Shimano Di2 wire EW-SD50 with external routing. This junction box is for mounting under the bottom bracket. Front/rear derailleur, cockpit area and battery are connected here.
(Only compatible with Dura Ace 9070, Ultegra 6770, XT 8050, Alfine Di2 und Nexus Di2. Not compatible with Dura Ace 7970 Di2).