The first coin below has an unusual cuirass. Constantius II is actually wearing it backwards. The curving part at the front of his neck should actually be at the back of his neck. I have seen a few other examples like this, but none to this extent. It seems that the engraver did not really understand what he was engraving...perhaps merely copying a right facing bust- the second picture shows the correct rendering of armor in relation to the direction the head is facing.