Security thread

Introduced in 1990, it consists of a thin ribbon that is woven through the note's paper.

[1][2] Usually, the ribbon runs vertically, and is "woven" into the paper, so that it at some places emerges on the front side and at the remaining places at the rear side of the paper.

It is made of metal foil, but sometimes of plastic, and oftentimes it has some text or numbers (e.g., the denomination) engraved.

The thread is a difficult feature to counterfeit, but some counterfeiters have been known to print a thin grey line or a thin line of varnish in the area of the thread.

[citation needed] Security threads can also be used as an anti-counterfeiting device in passports.