Jemstvenik
Jemstvenik or jamstvenik, is a string made of red, blue and white strands that is used to tie together official documents, and for similar purposes, in countries of former Yugoslavia, in a similar way to red tape in some common law countries.
The colors of the string are those of the flag of Serbia. It was later used in Yugoslavia, Croatia and Slovenia. Bosnia and Herzegovina and Montenegro still use the red-blue-white jemstvenik despite changing the flag colors. In North Macedonia, the string is called emstvenik and has the red-yellow colors of the flag of North Macedonia.
The term comes from the word "jemstvo"/"jamstvo" which means warranty.