Shimano's Dura-Ace Di2 Front Derailleur is the brains of their whole Di2 electronic shifting system. There's an ultra-compact CPU inside the beautiful carbon body that actually monitors the position of both derailleurs, ensuring that shifting is super fast, smooth and incredibly accurate shift after shift. It also creates a front derailleur that moves to maintain clearance between the chain and cage no matter what chainring/cog combination you choose (no rubbing or trimming). Even more impressive and important, this is the quickest shifting derailleur available meaning you'll never miss a shift again and will hit the right ring faster than ever. Thanks to no cables and housing to stretch, wear or fail, you'll also love Di2's amazingly smooth and silent operation.
Weight: 124 grams