The trojka is a very interesting instrument that was once made in Croatian Zagorje, but unfortunately it is completely obsolete today. It was created as a combination of the dvojnica and the sluškinja. Three holes would be drilled into one piece of wood – the left side would have no holes for playing, the middle would contain three (or four), and the right side would have four (or five). The manner of playing is similar to that of the sluškinja; two are played on, while the third tone is sometimes added while playing.