Shimano Ultegra Di2 STI Set ST-R8170 Hydraulic Flat Mount Disc Brake C

High performance Ultegra Wireless hydraulic Servo Wave disc brake Di2 STI's give you control, modulation and power with minimal effort in all riding conditions Wireless connectivity to the front and rear derailleurs for effortless trouble free gear shifts With Di2 technology shifting is easy and precise - just a light touch, as soft as a mouse click, is sufficient for the front or rear derailleur to instantaneously select the correct gear Full and semi synchronized shifting programable, Synchro shift compatible meaning a single shifter can control both front and rear shifting which can be fully custom tuned to your riding preferences. Semi synchronized shifting means when a front shift is made the rear mech will automatically correct to the appropriate ratio Simply pressing tactile buttons allows effortless and comfortable shifting even when your hands are cold Drop bar STI with shift buttons located in a near identical place to the positions you'd assume shifting using a mechanical Sh