The British Rail Class 03 locomotive was, together with the similar Class 04, one of British Railways' most successful 0-6-0 diesel-mechanical shunters. 230 were built at Doncaster and Swindon works between 1957 and 1962, and were numbered D2000–D2199 and D2370–D2399 (later 03004 to 03399). D2370 and D2371 were used as departmental locomotives and originally numbered 91 and 92 respectively.