Hybrid paper-polymer banknote

A hybrid paper-polymer banknote or composite substrate is a banknote made from a mixture of paper and polymer substance.
Hybrid banknotes are essentially a paper banknote with a polymer patch. A polymer patch/band is applied vertically over the entire height of paper banknote, thus creating a clear window. The height of the polymer window generally measures 74 mm × 16 mm. Its thickness is 25 micrometres. Bulgaria was the first country to produce a hybrid paper polymer banknote, in a denomination of 20 Bulgarian leva in 2005.
Manufacturers of hybrid banknotes include Giesecke+Devrient's Hybrid and Varifeye, De La Rue's Optiks, Louisenthal's Hybrid, Landqart AG's DuraSafe and Banque de France's EverFit.
The countries and monetary unions which use hybrid banknotes include: