When Shimano released the first generation Di2 electronic shifting system the battery charger system was sold in two parts: the charger, and an AC cable. This aggravated many folks, but Shimano rated the charger for worldwide use, and of course there are multiple wall plug formats used internationally. That continues today. This 2 meter long SM-BCC1-2 has the standard two-prong outlet plug used in the US and Canada and is rated and designed for both generations of Shimano Di2 chargers. So please, don't be offended, it is a modular system because Shimano is a truly international company.