The class 50000 consists of six six-car electric multiple units which have been built for the Nankai Airport Line that leads to the Kansai airport. This airport was opened in 1994 on an artificial island in Osaka Bay and is connected to the city by a road and rail bridge. The trains have been designed by Hiroyuki Wakabayashi with futuristic and retro elements. They have special streamlined noses and elliptic windows which resemble those of aircraft. Three of the inner four cars are being powered by four 180 kW three-phase traction motors each. Power was originally controlled by GTO thyristors, but they have been upgraded to IGBT in the meantime. The trains were generally painted in metallic deep navy blue, but over time some received special liveries. These include the themes Star Wars, Mobile Suit Gundam and the Osaka World Expo.