They were apparently not allocated to or built for any particular class of locomotive, but were suitable for use with a wide variety of serving engines.

[1][2] These tenders had a modern appearance, with flush sides all the way to the top of the coal bunker.

They were very similar in appearance to those Type XF tenders which had been rebuilt by the SAR by mounting a completely new upper structure on the existing underframes.

They had the same water capacity of 3,000 imperial gallons (13,600 litres) and coal capacity of 10 long tons (10.2 tonnes) as the Type XF, but rode on diamond frame bogies with a 12 inches (305 millimetres) longer wheelbase per bogie.

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