The eps rear derailleur is comprised mainly of a mechanical structure derived from the mechanical gear and composed of a derailleur rodparallelogramderailleur cage of a worm screw enabled by an electronic actuator as with the derailleur the electronic rear derailleur actuator is composed of a gear motor and a sensor the built in resolver that reads its movements the geometry of the parallelogram has been made more rigid and optimised to promote interaction with the electronic parts the