The so-called "Kaminski pattern."
A later "MODEL" overprint made on a circulating banknote, with running numbering, most likely in the 1970s.
Although these are not the original designs of the era, they are well established on the market as a kind of"historical forgery" to the detriment of collectors, one of the first to be made for the paper money market. Most often found on Polish marks, for other issues rarer.
