JHA OK19353 at Watford Junction in June 2008. ©Hugh Llewelyn
The O&K JHA Hopper wagons were built to coincide with the introduction of the Class 59s in the UK for aggregate haulage operations with Foster Yeoman. They remain in service to this day with Mendip Rail. A rake of these wagons consist of two outer wagons and a number of inner wagons. The notable feature is that the two outer wagons have screw-link couplings and buffers on the outer most edge of the train, whilst the connection between the inner wagons is via a buckeye-style coupling allowing for closer coupling and hence an overall reduction in the length of the train, which was considered to be an important design aim.