Pi so, a length of bamboo with seven fingerholes (no thumbhole). The metal free is set into the wall of the proximal end which is closed by the septum. Made in Chiang Mai.
The pi so is a free reed pipe used in the folk music of north-western Thailand. It is often used to accompany singing. The player's mouth completely covers the reed, and the pipe is played while both inhaling and exhaling, much like the playing technique for a Western mouth organ. This instrument was acquired in Chiang Mai.