The R2C designation of the SRAM TT shifters means Return to Center. This means that every time you shift, the trigger moves back to the same position, so each shift is exactly the same movement and you don't need to contort your hands to make sure the shifters are all the way engaged in the next gear. To customize the shifters to your ideal hand position, the center position is adjustable. The shifters were built from carbon and are compatible with SRAM double front chainrings and 11-speed rear cassette.