In the effort of multiple European railways to develop diesel trainsets for TEE service, the Dutch NS and the Swiss SBB worked together. The result was called DE IV by the NS and RAm TEE by the SBB. Each set consisted of a power car, a pure passenger coach, a combined seating and dining coach and a control car with seats. In total six sets were built of which three were owned by the NS and two by the SBB. They were operated together by both companies and used on the TEE lines between Amsterdam and Zurich and between Paris and Brussels.

The power cars were built by Werkspoor in the Netherlands and the coaches were built by SIG in Switzerland. Both received their electrical equipment from BBC. The power cars had two 1,000 hp sixteen-cylinder diesels each with electrical power transmission. For train supply, there was an additional 300 hp diesel with its own generator. Due to the weight of their equipment, the power cars had two three-axle bogies of which the two outer axles were powered.

When the TEE services in France were changed to loco-hauled trains, they also operated between Munich and Zurich. In 1971, RAm 501 was lost in a crash at Aitrang. The remaining four sets were withdrawn in 1974 and sold to a Canadian operator. After they had been shipped and modified for use in North America, they were leased to the Ontario Northland Railway and used as “Northlander” from 1976. Due to problems coming from the harsh climate conditions in Canada, the motor cars were replaced by EMD FP7 diesel locomotives in 1979 and scrapped. In 1996 five of the cars were brought back to Europe. None was refurbished into working condition, but some later came to museums.