[3] A number, when added after the letter code, indicates differences between similar tender types, such as function, wheelbase or coal bunker capacity.

[3] Builder's works pictures of the Classes 6B and 6E show them with the same 5 long tons 10 hundredweight (5.6 tonnes) coal capacity Type XC1 tender.

Early versions of the built-up coal bunker sides were in the form of a slatted open-top cage, made of rectangular steel rods.

In the second example depicted, one of the four CGR locomotives which were sold to the Benguela Railway in Angola in 1907 is shown with a Type XC1 tender with such a slatted extension of extraordinary proportions.

[2][3] From c. 1925, some of the Type XC1 tenders were rebuilt by the SAR by mounting a completely new upper structure on the existing underframe, with new water tanks and a larger coal capacity.

Collins DSO, who approved several of the detailed drawings for the work during his term in office as Chief Mechanical Engineer of the SAR from 1922 to 1929.