All 1945 Slovenian provisional issues were overprinted in enviably high quality. That is a reason for a small number of errors and specialties that are available today. Therefore, I was pleasantly surprised when I found the entire sheet of Maribor issue with very large slanting overprint.
1945 Maribor local provisional issue, entire sheet of 12pf (Mi. 8) with large slanting overprint.
Extract of the overprint.
Lower right detail, showing one overprint extended to four adjacent stamps.