These units were intended for operation in South West Africa (SWA), now Namibia, under very light rail conditions which necessitated lighter axle loadings, which could not be achieved with conventional Co bogies under a heavy locomotive.
In South Africa, this virtually opened the floodgates for GE, since more than half of the SAR's vast diesel-electric locomotive fleet, which was acquired between 1959 and 1981, were GE products [REF].