Well, the mortar platoon in each battalion will tow a few 120mm
pieces into battle.... a sort of a small-scale artillery to be used
at the CO's disposal, if you will.
81mm is the NATO standard, I believe.... I remember reading that
the Soviets created the 82mm mortar in response to the NATO 81mm.
The theory goes that the Soviets would be able to use captured NATO
mortar shells (albeit to a low degree of accuracy), whereas the
NATO troops wouldn't be able to make use of captured Soviet mortar
shells.
60mm? I don't think that has ever been used in the SAF.