Despite its smaller, lighter design, the Dura-Ace FD-R9250 brings the fastest front shifting on the market. The fastest just got faster thanks to the Dura-Ace FD-R9250. Tipping the scales under 100 grams, the new design shifts 45% quicker than Shimano's FD-R9150, already the fastest on the market. And the frontal area of the FD-R9250 is also reduced to decrease aerodynamic drag. Shimano Di2 Electronic Drivetrain Performance Thanks to its lightning-fast, accurate, and reliable shifting performance, Di2 puts riders in complete control and ensures a seamless interface between the cyclist and bike like never before. Creating and continually improving the world's best shifting is a complicated undertaking requiring constant technological advancements. From hardware to software, Shimano Di2 technology is on the cutting edge, striving to deliver the best rider experience possible now and in the future. Shimano E-Tube Compatible E-Tube is Shimano's “service” that uses websites or apps to maximize the enjoyment of riding a bicycle by connecting the riders, the bicycles and Shimano. Shimano's genuine application E-Tube Project for Mobile allows you to customize your bike, update firmware, and maintain it by connecting it wirelessly to your bike. You can also get more detailed bike maintenance by connecting to your bike by wire with E-Tube Project via the Windows V4 application. HYPERGLIDE+ Optimised HYPERGLIDE+ dedicated chain technology delivers greater chain retention, improved shifting efficiency, and smoother transmission over rough terrain. Improved chain retention encourages more aggressive all-terrain riding and relieves chain-issue anxiety. Smoother drivetrain transmission and enhanced shifting performance sharpens riders’ concentration and improves acceleration. Better chain engagement cuts abrasion, reduces maintenance, and lengthens the lifespan of the chain.