The vz.50 pistol was a compact .32 ACP (7.65mm Browning) double action pocket pistol used by police forces. It was given a face lift and redesigned the vz.70, and there were plans at one point to further modernize it. The new design would have been the vz.80, but only a few prototypes were made - one of which we are looking at today from the CZ reference library. The would-be vz.80 has a barrel about 1cm shorter than the vz.50/70, and a revised mechanism for removing the slide. And other than a few cosmetic changes to parts like the safety, that's it...