The Shimano 105 ST-R7170 Di2 Shift/Brake lever features Di2 electronic shifting for precise intuitive gear changes to even more riders. The 105 BR-R7170 caliper features the Shimano Flat Mount System and its low-profile design that is ideal for road bikes.Reach adjustment and customized button functions allow you to dial in your ideal ergonomicsCreates a clean cockpit with wireless connection and enhances the aesthetic of your bike while keeping shifting lightning fastEasily change button function with the E-TUBE appIncludes 2 x CR1632 batteries10% wider pad clearance decreases the chance of disc brake rotor rubMaintenance-friendly one way bleeding processIncludes L03A Resin pads with finned alloy backplate