Due to the demand for larger goods engines, the 355 Class was designed by the GSWR. However, due to a strike at their railway works at Inchicore, the engines were instead built by the North British Locomotive Company, Glasgow in 1903. However, after arrival, the GSWR noticed the engines were forward heavy and were prone to derailments. All engines were then rebuilt in 1907/8 as 2-6-0s which solved the derailment issues. Includes AJS Script.