SHIMANO Ultegra Di2 Road Bicycle Front Derailleur - FD-6870 Shimano Electronic Intelligence System allows accurate and effortless shifting in challenging circumstances, plus it'll never be affected by contaminated or stretched cables, since the shifting signal is transferred electronically E-TUBE offers optimum on-the-bike flexibility: Transmits interactive signals and power supply to each part by &quot;Plug &amp; Play&quot; connection No rust, no stretch, no freezing and advanced low maintenance SM-PCE1 connects between PC and components to update firmware