Intercity Rolling Stock) is an electric multiple unit (EMU) train type operated by the Nederlandse Spoorwegen in the Netherlands.

The train received the nickname Koploper, because it had a so-called "walk through head".

The trains run daily on the Dutch rail network and, together with the VIRM, form the most important equipment on services connecting the Randstad with the rest of the country.

It has since been converted back to a regular carriage, but it continued carrying number 4444 at first.

When ICM units joined, the doors at the end of the train would open, and a walkway would emerge, coupling with the other set and allowing passengers and crew to walk through to the next set.

The reason given was that they were not often used, but they also had many technical problems that made the trains late on a regular basis.

During their refurbishment from 2006 onwards, these hallways were permanently sealed shut and the doors at the heads of the train were replaced by a light polyester plate, saving the NS maintenance costs.

The first train left NedTrain's workshop in Haarlem in April 2007 and then put into the regular service.

Other improvement include the addition of a wheelchair toilet, air conditioning, OBIS, and digital travel information.

On the exterior, the train sets were repainted showing blue window surrounds curving at the ends of units.