Campagnolo Electronic Power Shift operates on a lithium ion battery in its Power Unit that can go longer between charges than any other battery in the business. But all good things must come to an end, and you can count on your battery running out of juice someday. For the charge that will get you back on the road, you need the Campagnolo EPS Charger Cable to connect the EPS Charger (sold separately) to the Power Unit.