The South African type XJ tender was a steam locomotive tender. Two Type XJ tenders entered service in 1911, as tenders to the two Mountain type steam locomotives which were acquired by the Cape Government Railways in that year. These locomotives were designated Class 4 on the South African Railways in 1912. Manufacturer Type XJ tenders were built by the North British Locomotive Company in 1911. The Cape Government Railways (CGR) placed two Mountain type steam locomotives in service in 1911, designed by CGR Chief Locomotive Superintendent H.M. Beatty at the Salt River works in Cape Town. These locomotives were designated Class 4 on the South African Railways (SAR) in 1912. The Type XJ entered service as tenders to these two engines. Characteristics The tender had a coal capacity of , a water capacity of and a maximum axle load of . Locomotive In the SAR years, tenders were numbered for the engines they were delivered with. In most cases, an oval number plate, bearing the engine number and often also the tender type, would be attached to the rear end of the tender. During the classification and renumbering of locomotives onto the SAR roster in 1912, no separate classification and renumbering list was published for tenders, which should have been renumbered according to the locomotive renumbering list. Only the two Class 4 locomotives were delivered new with Type XJ tenders, which were numbered 1477 and 1478 for their engines. Classification letters Since many tender types are interchangeable between different locomotive classes and types, a tender classification system was adopted by the SAR. The first letter of the tender type indicates the classes of engines to which it can be coupled. The "X_" tenders could be used with the following locomotive classes: CGR Mountain, SAR Class 4. SAR Class 4A. SAR Class 5. CGR 6th Class of 1897, SAR Class 6B. Oranje-Vrijstaat Gouwerment-Spoorwegen 6th Class L3, SAR Class 6E. CGR 6th Class of 1901 (Neilson, Reid), SAR Class 6H. CGR 6th Class of 1902, SAR Class 6J. CGR 8th Class of 1902, SAR Class 8. Imperial Military Railways 8th Class, SAR Class 8A. Central South African Railways Class 8-L2, SAR Class 8B. Central South African Railways Class 8-L3, SAR Class 8C. CGR 8th Class 4-8-0 of 1903, SAR Class 8D. CGR 8th Class Experimental, SAR Class 8E. CGR 8th Class 4-8-0 of 1904, SAR Class 8F. CGR 8th Class 2-8-0