Sram ex1 x actuation trigger shiftersrams ex1 trigger shifter is specifically tuned for use with e mtb bikes power assisted drivetrains and as its equipped with srams x actuation technology shifts are precise fast and efficient its also specifically tuned to deliver one accurate shift at a time so you avoid over shifting to the wrong gear thus extending your e mtbs battery life and decreasing component wear and tear features recommended groupsram red etap speed 8 speed recomme