Shimano SM-EW90-B Di2 Junction A 5 Port for TTWith Shimano's simplified and improved front junction box (junction A) for 9070 Dura Ace Di2 and 6870 Ultegra Di2, you now have 5 ports for use with both drop bar and TT shifters simultaneously. The new 9070 unit utilizes a rubber strap that cleanly and aerodynamically fastens underneath the stem. Better still, the 5 port junction box has a charging port that makes it possible to charge both internal and external batteries without having to remove