The souravli is a type of duct-flute made of peg or wood. It has a 2 octave ambitus

Ambitus (music)

Ambitus is a Latin term literally meaning "the going round", and in Medieval Latin means the "course" of a melodic line, most usually referring to the range of scale degrees attributed to a given mode, particularly in Gregorian chant. It may also refer to the range of a voice, instrument, or piece...

 and its opening is slanted to the edge.

A double flute is called a disavli (δισαύλι), one with no holes and the other one having holes to play the melody.

In Cyclades

Cyclades

The Cyclades is a Greek island group in the Aegean Sea, south-east of the mainland of Greece; and a former administrative prefecture of Greece. They are one of the island groups which constitute the Aegean archipelago. The name refers to the islands around the sacred island of Delos...

, the souravli is very widespread, especially in the Greek island of Naxos

Naxos (island)

Naxos is a Greek island, the largest island in the Cyclades island group in the Aegean. It was the centre of archaic Cycladic culture....

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