Shimano dura ace di2 dual integrated intelligence r671 are the next generation of tttri shifters put to the test in competition and used in victory by pro cyclists in every conditions including road across the pav or mud these 11 speed shifters have even been used by the 2012 tour de france team sky triathletes and time trial cyclists wont need to choose a different shifter position as di2 makes multiple shift controls possible the tttri shifters can be used on the base bars and sa