The NS Mat '64 or Materieel '64 were electric multiple units (EMU) built by Werkspoor and later by Duewag and Waggonfabrik Talbot between 1961 and 1976. They were operated in the Netherlands by the Nederlandse Spoorwegen (NS) until 2016. The equipment consisted of independent four and two-car train sets called Plan T and Plan V: the Plan T is a 4-car EMU, and the Plan V is a 2-car EMU. Materieel '64 is sometimes nicknamed 'Apekoppen' (literal translation: 'monkey heads') and 'Standaard Stoptrein' ('Standard slow train') due to their distinct shape. Plan V was, for many years, with 246 units (although only 245 were present at the same time), the largest series of Nederlandse Spoorwegen rolling stock, until the arrival of the VIRM. A number of train sets were also leased to and used by various regional carriers. Materieel '64 has been in service for 55 years, from 1961 to 2016, on the Dutch railway network. Appearance The Materieel '64 rolling stock has a convex nose, like the Materieel '54 rolling stock, to protect the train operator in case of an accident. It, however, sticks out less far than the Materieel '54 rolling stock and looks more like the Plan U rolling stock nose. Originally, Plan T and the 30 oldest Plan V train sets were green with a light yellow band. From the in 1968 delivered 431 train set onwards, they were delivered in the new NS color scheme, which consisted of a yellow with gray and slanted blue advertising tracks. The reason for this, was to give the railways a new impetus in the context of Spoorslag '70. The older green train sets also received the new color scheme in the following years. Manufacturing The Materieel '64 prototype, Plan TT (Treinstel Toekomst, translation: 'Trainset Future') 501, was built by Werkspoor in 1961. In the years 1964-1965 the follow-up series Plan T was built and delivered in three partial series. Most trains where scrapped. Plan V was delivered in 13 partial series in ten years (from 1966 to 1976). The first train set was already scrapped before the last train sets were delivered. The last two series (V12 and V13) are as old or even newer than the oldest SGM train sets. As of 2016, all of the train sets have been put out of service. Design The Materieel '64 design is derived from the DMU Plan U, which