Original: They were divided into two batches: those built at BR's Swindon works were numbered in the series D800 to D832 and from D866 to D870, had a maximum tractive effort of 52400 l and eventually became British Rail Class 42.
Simplified: They were divided into two batches: examples built at BR's Swindon works were numbered in the series D800 to D832 and from D866 to D870, had a maximum tractive effort of 52,400 pounds force and are the British Rail Class 42 of this article.