The 12XP has been produced in parallel with the 12 (but for a longer time), and in much greater quantity. The display uses LEDs while it uses a needle for the 12.
Zenit 12SD, given by Adrien K. Received march 15th, 2014.
For the Soviet market, The 12xp was called 12sd, but it was renamed for export, SD being the name of the secret service of Nazi Germany.