The Çifteli (Definite Albanian form: Çiftelia) is an Albanian wooden, largely acoustic string instrument, with only two strings (in Albanian, çifteli means "paired").
The çifteli is commonly used by Albanian folk musicians as well as other modern musicians and is played by Albanians at weddings, concerts, national events, and other occasions. Especially important is its role in the accompanying of the Albanian epic ballads.
The size and scale length of various Çiftelias may differ from one another. The Çifteli is often tuned to that of the same pitch as the two highest strings on the guitar, strings E and B. Usually the lower string is played as a drone, with the melody played on the higher string. The Çiftelia is a fretted instrument, but unlike most it does not have one fret per semitone, but rather one fret per note in a seven note diatonic scale. Seven frets up is the octave of the open string.
Source: en.wikipedia.org/wiki/%C3%87iftelia