This is a money holder if you want to troll a little while being nice. It will fit a few US bills rolled up tightly, then stuffed in through either end. It's easy to get the money in, but takes some effort to get it out.
Can be printed in your filament of choice. I recommend petg or pla for ease of printing and 100% infill or up your perimeters so that there's no infill. It is possible to just break it open, but that's no fun.
The author hasn't provided the model origin yet.