 On 11 October 1899, Neilsons contacted the South Eastern and Chatham Railway (SECR), which had recently placed a locomotive order with them.The SECR was an organisation which had been formed on 1 January 1899, and which was short of express passenger locomotives for the former London, Chatham and Dover Railway routes, which had a weight limit.The SECR quickly accepted the offer, paying £3200 each for them, whereas Neilsons would have charged the GNSR £2975 each; in December, the cost to the SECR was increased by a further £57 per engine and tender after Harry Wainwright, the SECR Locomotive Superintendent, requested modifications including the fitting of vacuum brake equipment.