During the Second Boer War, the British troops urgently needed powerful tank locomotives. Since the Natal Government Railways had already procured a ten-coupled tank locomotive from British production, the Reid Tenwheeler, they used this design and ordered 35 units as well. The order was divided between Dübs and Neilson, Reid in order to achieve a larger number in a short time. A visible difference to the NGR locomotives was the weatherboard on the coal bunker, which also offered protection from the elements when reversing. The military locomotives also attracted attention due to the brass parts on the boiler which were always polished to a high gloss.

The first and fifth driving axles were designed without wheel flanges for better flexibility, which, however, was fatal to the locomotives in some situations. Especially when reversing, there were often derailments when entering tight curves or switches because the leading coupled axle had no wheel flanges. One attempted solution was to widen the wheel tyres, but this had only limited success. Despite this problem, the locomotives provided valuable service during the war until they came to the CSAR at the end of the war.

In order to really improve negotiation of curves and prevent derailments, the CSAR like the NGR decided to remove the fifth driving axle and thus convert six of the locomotives into a 4-8-2T. A very large distance between the fourth driving axle and the trailing axle was now visible, and the load on the trailing axle increased from just over four to just over six tons. With the formation of South African Railways they became class E as tank locomotives were designated with letters. They were mainly used for shunting and were retired by 1966.

Another rebuild was carried out in 1904 initially on one locomotive to increase the range, since this was too short in the eyes of the SAR. The last driving axle and the trailing axle were removed together with the coal bunker, the frame was shortened accordingly and an additional tender was attached. Since the water tanks on the sides of the boiler had been retained, it was a 4-8-0TT tank-and-tender locomotive.

Since the second rebuild was successful, all remaining 28 locomotives were rebuilt in the same form and provided with surplus three-axle tenders. In the SAR they received the class number 13, since tender locomotives were designated with numbers. They were mostly used in the Witwatersrand region, where they were nicknamed “wallopers”, which means “wall runners” in Afrikaans. After their withdrawal, which was completed by 1961, some were sold to various mine operators. Some of these locomotives were used until the 1980s, after the side tanks had been removed from some in the meantime.