Cái kèn đôi (gender unknown)
Hornpipe without a mouthpiece: single chanter, bell / single reed (type?)
Composed of 2 Cái kèn một (a primitive cane clarinet; Một = "one (1) / single"; Đôi = "double"), pasted together with resin; Poor spelling (Cái ken dôi / ~ môt) in Sachs, according to whom the instrument is used for funerals only.
Sachs, Curt: Real-Lexikon der Musikinstrumente: zugleich ein Polyglossar für das gesamte Instrumentengebiet [Berlin, 1913]. Hildesheim, 1964 [facsimile].
Širola, Božidar: Sviraljke s udarnim jezičkom [Aerophones with a beating tongue]. Zagreb, 1937, p.92, 109.