This product can be converted to wireless electric shifting without changing the existing rear derailleur!
It is an epoch-making shifting system that makes all adjustments with a smartphone app. (As of February 17, 2019, Android is not supported.)
A microcomputer-controlled operation system is attached to the conventional rear derailleur for wireless electric shifting. Since the wire can be adjusted in 0.1 mm increments for each gear, the shifting touch is dramatically improved. You can easily adjust all the wires and check the battery level with the smartphone app. With Japanese version manual.