As with most of the surface-rate international issues, this one is a difficult example to find properly used. This issue is neat because it supported both the international and domestic postal card rates, although originally designed and issued for the former.
This one has had a particularly interesting travel history as modern-era postal cards go. Originally destined for Vienna, Austria, for some reason it wound up going to El Salvador! Now, how could that have happened? I'm glad it did, because the card received a nice auxiliary evidencing the mix-up. It wound up taking over a month to get to the correct destination!
Place mouse on image to see the reverse side of the card.