“Day 100: This is a 4 note set issued on May 1st, 1919 in the city of Berncastel. There are many things that make this a special set. First off, these notes were only valid for 2 days—from May 1st, 1919 -> May 2nd, 1919. These were the dates of a Circus and County Fair being thrown for the 90th Infantry Division in Berncastel, Germany, and this Notgeld was printed specifically for use at the fair.
Another thing that makes this set special is that every note is written in English without any German words used. I believe this characteristic to be unique amongst all German Notgeld. Since these notes were intended to appeal to an American audience, the imagery used was also geared towards classic American imagery like Native Americans, cowboys, etc.
Lastly, another unique characteristic of this set is the denominations used. Instead of "Pfennig", "Marks", "Cents" or "Dollars"—the value of these notes is denoted in "TO's" or "Teeohs". “TO” comes from “Tough Ombres”, a nickname derived from the name “Texas-Oklahoma Division” / 90th Infantry Division. Therefore, the four denominations used in this set are 10 Teeohs, 20 Teeohs, 50 Teeohs, and 100 Teeohs.
The value of this very scarce complete set of 4 notes, in this condition, is $2,000+. Here you can find more info about this set and others.”