You show a transparent plastic strip provided with holes, and a black container provided with holes. You slide the transparent strip in the black holder so that the holes are exactly alike. Then you take a needle with thread and thread it six times through the different holes to thread the two plates together. Yet you can despite the string the plastic strip now pull out the black holder!

Everything must now be examined, very easy to show, complete with holder, strip, needle, thread and instructions. Playing shown in the photo is just to show the size of the entire unit and is not supplied (nor necessary ...).