The M250 was designed for moving light parcels faster than regular freight trains could to. Therefore it is an electric multiple unit that can carry containers at a speed of up to 130 km/h. Each set consists of 16 cars, of which the first two on each end are being powered by four 220 kW three-phase traction motors each. Each of the motors has its own inverter. These cars can only carry a single 31-foot container and have crew and equipment rooms on both ends. For the first time in any vehicle of JR Freight, the cabs had a combined power and brake lever. The twelve flat cars in the middle of the train can carry two 31-foot containers each, what makes a total of 28 containers per train. Kawasaki, Nippon Sharyō and Toshiba built two full sets in 2002 and 2003, along with a total of ten spare cars. They are officially being dubbed “Super Rail Cargo” and are being operated by Sagawa Express between Tokyo and Osaka.

One of the secondary lines in Bavaria operated by the LAG was the one between Türkheim and Bad Wörishofen. This line had already been electrified with 550 V DC when it was opened in 1896. After the original two passenger railcars, the LAG built a two-axle freight railcar from an old baggage car. The electric equipment came from SSW. Like its predecessors, it had two traction motors with 55 kW each and reached a top speed of 40 km/h. The Reichsbahn numbered it ET 194 11. It was in use until 1939 when electric service was discontinued. After this, it came to the Bad Aibling - Feilnbach line, but was only stored until it was finally scrapped in 1947.

With the introduction of the light steel wagons, the SBB planned to operate the city express train between Geneva and Rorschach with short, light trains. For this purpose, three baggage railcars were initially ordered, which had an output of almost 1,000 kW and a top speed of 125 km/h. Thanks to the BBC spring drive, good suspension properties could be achieved at higher speeds. Since the space required for the electrical equipment was limited due to the relatively low output, there was sufficient space in the car body for the luggage compartment.

During the Second World War the volume of traffic increased sharply and it was not to be expected that it would decrease again after the end of the war. Although the RFe 4/4 had multiple controls and gangways, operation with two or three baggage railcars distributed across the train was not optimal. Thus, the development of a pure, more powerful electric locomotive was commissioned, from which the Re 4/4 I emerged.

Thus, no further orders followed and the three pieces were sold in 1944. Both new operators underwent a conversion of the railcars, during which some problems that had arisen were fixed and the maximum speed was reduced to 90 km/h with a new gear ratio. The weight had increased by 3.5 tonnes. With the conversion, the designation was changed to Fe 4/4 and from 1962 it changed to De 4/4.

The first example with the number 601 ended up on the Bodensee-Toggenburg railway and was used there until 1977. Then it came to the Sihltal-Zürich-Uetliberg-Bahn. It has been used as a historic vehicle since it was sold to the Oensingen-Balsthal-Bahn in 1994.

The other two examples, numbered 602 and 603, were sold to the Swiss Southeast Railway in 1944. Two suitable control cars were built there in order to be able to use them together with a motor car and a trailer as a shuttle train. The last use took place in 1993 and 1994 respectively. While the 602 was scrapped in 1997, the 603 is now owned by Swisstrain together with the 601 and serves as a spare parts donor for them.