[1] It was strongly focused on the rights of white workers, and sought to exclude others from working as moulders.
In 1913, one "coloured" moulder was admitted to the union, against the opposition of some members, on the grounds that he presented as being white.
It also campaigned for higher wages, longer holidays, and against piece work.
The majority were white, but a substantial minority were now "coloured" or Asian.
[1] In 1995, it merged with the Amalgamated Engineering Union of South Africa, the Engineering, Industrial and Mining Workers' Union, and the South African Boilermakers' Society, to form the National Employees' Trade Union.