Clones are a Transformer pairs that are created to be physically identical in their robot forms, although they have unique alternate modes. It is unclear what purpose this serves, other than perhaps to conserve resources by mass-producing bodies or to instill an element of surprise, since one can't be sure which clone one is facing on the battlefield. Or it's just possible that someone was plain lazy.
Known clone pairs are:
Released in 1987, both pairs were only available as part of a two-pack set. Each clone came with a pair of rifles and two rubsign insignias, one identifying their faction and the other to distinguish the two by revealing an image of their unique alt-mode. Due to the requirement of identical robot modes, at least when viewed from the front, Clones are a good example of Transformer toys with non-integrated alt-mode kibble sticking out of their backs.