The 2005 railhead treatment train (RHTT) season marked a major step in Network Rail’s modernisation, introducing purpose-built FEA-F wagons and replacing an assortment of ageing second-hand vehicles. Fifty 60-ft flats, built in Poland by Greenbrier Europe, were numbered 642001–642050 and designed to carry modular equipment, allowing retirement of General Utility Vans and TTA water tanks. Earlier KFA wagons had already introduced large water tanks and high-pressure jetting systems, later supplemented by Sandite applicators capable of operating at up to 60mph.