The Campagnolo Chorus EPS groupset takes a great deal of its DNA from its mechanical counterpart as it represents a more accessible version of Campagnolo performance, quality and attention to detail but delivers it in the laser-like precision package of an EPS drivetrain. The internal power unit also improves system integrity with the EPS processor and power unit safely tucked away from possible impact or contamination from outside elements.With an IP67 waterproof rating on the entire system rain gear is only necessary for the cyclist, not his groupset. The new EPS(TM) V2 Power Unit is an improvement with regards to aerodynamics, versatility, durability and protection but also plays a pivotal role in an aspect that is not to be overlooked; aesthetics. The new EPS(TM) V2 Power Unit gives the cyclist the possibility to use the most advanced groupset while maintaining sleekest look to his or her ride. The brain of the system. The EPS(TM) Power Unit(TM) is much more than just a battery. Its housing contains all the electronics of the EPS(TM) drivetrain, the system memory input/output gates and the battery charger plug. This design choice benefits both the reliability and the performance of the system, which is also upgradeable.