Among operators in the military it's common practice to possess unit "zaps" with which to mark your visit to other units and to indicate your passage through the bars of the world. Mrs B has found this zap of the Ukraine Air Force while cleaning out children's toys in preparation for a family visit.
I can't remember ever visiting such a unit, nor being visited; except that in my last frontline tour, at RAF Brüggen in Germany, we had several visits by delegates from countries of the former Soviet Union to demonstrate transparency under the Open Skies agreements. We must have had a visit from Ukraine, among which will have been an Air Force officer or two.
I hope that I was a congenial host . . .