Shimano Dura-Ace ST-R9270 Di2 STI Hydraulic Disc Lever Left With a raised hood profile and longer hood body, the left Shimano Dura-Ace ST-R9270 Di2 STI Hydraulic Disc Lever offers more comfort and support throughout various hand positions. The hood body houses the wireless hardware that communicates in a lightning-fast manner with the derailleurs just a light touch of the intuitively positioned gear-change buttons on the side of the lever activates the wireless signal, prompting smooth and rapid gear shifts. The unit is powered by a small CR1632 battery that lasts for approximately 1.5-2 years, while ports for additional satellite shifters are integrated to offer even more shifting options. Typically operating the front derailleur, the shifting behaviour of this left-hand lever can be fully customised via the E-TUBE Di2 app. Enhanced braking performance is provided by the carbon lever and its integrated Servo Wave technology that minimises empty lever travel, but increases feel once the pads contact the rotor. In addition, the hydraulic reservoir is self-adjusting to keep the pad spacing consistent as they wear, and a lever reach feature ensures that all hand sizes can comfortably clasp and operate the brakes effectively.