Hornbostel - Sachs
Stopped single end-blown flutes
The air itself is the vibrator in the primary sense. The standing waves are significantly confined within the instrument itself. The player creates a ribbon-shaped stream of air with his/her lips, blowing against the sharp rim at the upper open end of a single tube. The lower end of the flute is closed. The instrument has no fingerholes. The bore of a key.
Stopped single end-blown flutes without fingerholes
Stopped end-blown flutes without fingerholes used in sets