K'ny is a single string bowed instrument from Central Vietnam. The one attachment is tied with that string and it makes a variety of sound following the mouth shape of the player who is  rubbing the string with a bow.
<a href="//commons.wikimedia.org/w/index.php?title=User:DTH-BD-NVT&amp;action=edit&amp;redlink=1" class="new" title="User:DTH-BD-NVT (page does not exist)">Junichi Usui</a>
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<span class="int-own-work" lang="en">Own work</span>