Shimano has simplified and improved the front junction box (junction A) for 9070 Dura Ace Di2 and now it has 5 ports. The SM-EW90 5-Port Junction Box combines the function of the 7970 j-box with the cable housing mounted battery status/adjustment module for a simpler, cleaner installation. The 9070 junction box no longer uses unsightly zip ties to connect to brake cables like Shimano has used in the past. The new 9070 unit utilizes a rubber strap that cleanly and aerodynamically fastens underneath the stem. Better still, the 3-port junction box has a charging port that makes it possible to charge both internal and external batteries without having to remove them from the bike. The single adjustment button from the 7970 unit remains and functions just as simply as it always has. Lighter, cleaner, better... Dura Ace Di2 9070.
Actual weight: 11g
5-port junction box
Battery charging port for use with Shimano ISMBCR2 charger
2 Rubber mounting straps included