This ship was originally built in 1907 as the Heliopolis for the British-owned Egyptian Mail Company. She was 11,146 GRT with a length of 525.8 feet (160.3 metres), a beam of 60.2 feet (18.3 metres), two funnels, two masts, and a triple-screw propulsion that gave a cruising speed of 19 knots (35 km/h).
The Kiha 56 series Express Diesel Car was launched from 1961 for improved "smokeless" express service in Hokkaido, and was similar to the Kiha 58 series developed at the same time and built from 1961 to 1969 by different manufacturers. The KiHa 56 was designed to increase resistance against extreme cold, and all the saloons had double-glazed side windows with excellent heat retention. Furthermore, the vertical height of the cabin windows was 100 mm less than with the Kiha 58 series.
A total of 111 of this Px48 class were built between 1950 and 1955, mainly for 750 mm gauge, some were later rebuilt for metre gauge. One was bought by a NZ businessman in 1992 and placed on a short section of track in Raratonga in the Cook Islands.