The South African Railways Class 20 2-10-2 of 1935 was a steam locomotive. In 1935, the South African Railways placed one Class 20 steam locomotive with a 2-10-2 Santa Fe type wheel arrangement in service, designed and built at its Pretoria Mechanical Shops. In 1950, it was modified to an experimental condensing locomotive. The Class 20 was the third locomotive type to be designed and built in South Africa, after the Natal Government Railways 4-6-2TT Havelock of 1888 and the Class 2C of 1910.