E217系を中心に掲載しています。
Series E217 was designed for the Yokosuka/Sobu Line rapid service. Although running more than 100 km, it has as many doors as commuter trains such as Series 209. Since it passes through the Tokyo tunnel near Tokyo Station, it has a front-end emergency door as required for underground operation. Several trainsets were later transferred to the Tokaido Line. Every trainset contains two double-decker Green Cars, which offer better accommodation for an additional charge.