The British Rail Class 10 diesel locomotive was a variation on the Class 08 diesel-electric shunter in which a Blackstone diesel engine was fitted instead of one made by the English Electric company. Traction motors were by the General Electric Company plc (GEC); the class D3/5 were similar, but had British Thomson-Houston (BTH) traction motorsThe locomotives were built at the BR Works in Darlington and Doncaster over the period 1955–1962.