Image: Khlui Phiang O Flute from Thailand
This flute is from the collection of the Museum of Fine Arts, Boston. It is listed by the museum as a Khlui Phiang O (Khlui, middle size) from Thailand, early 20th century. It measures 41.1 cm × 2.6 cm (16 9⁄16″ × 1"), made of bamboo. Item 183239, Accession number 2004.412.
This view is the back side of the instrument, with the true sound hole near the top, a thumb hole for the upper hand, and one of the tuning holes near the bottom.
See World Flutes for more context about this image.