The MRA side tipping ballast wagon ran in fixed rakes of five wagons, one of which was fitted with a generator to provide power and air for the whole set. Each wagon had two shallow boxes which could be tipped to either side, discharging ballast onto parallel track beds. The first batch of 300 wagons (60 sets) was made by Thrall Europa in York between 2000 and 2002 and was liveried in cream and blue of Railtrack. A second batch of 100 wagons (20 sets) was made by Trinity Rail in Romania in 2004 and brand in yellow Engineers livery of Network Rail. in 2006 five sets were transferred to GB Railfreight to work on its Metronet track removal contract. From 2023 a program to convert a significant portion of the MRA fleet into JNA-Y wagons has been undertaken.