Top of the range, high performance Dura-Ace hydraulic disc brake Di2 TT STI\'s give you control, modulation and power with minimal effort in all riding conditions 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 The removal of traditional mechanical cables in favour of electrical wires eliminates poor shifting caused by contaminates, corrosion and stretching, and also provides effortless gear shifts Full synchronized shifting programable, Synchro shift compatible meaning a single shifter button either side can control both front and rear shifting which can be fully custom tuned to your riding preferences TT STI with one shift button each side Shifters are lightweight thanks to carbon fibre lever blades and carbon composite bracket body Hydraulic brake lever provides excellent stopping power with less effort especially from the hood position Hydraulic reservoir tank provides pad to rotor clearance auto-adjust maintaining braking performance during pad wear Finely tuneable reach adjusters for the levers enable custom fitment for all hands Free stroke adjustment for pad to rotor contact setting Levers are supplied without electrical cables, as these need to be ordered separately to suit