From the Loftsmith community

Songbird whistle (support-free)

A little bird you can blow into, with a hole in its head for a string or keyring. The body is a round chamber with a long flat tail you hold in your lips, and a small wing is etched on top. Change the chamber size to make the note higher or lower.

1 part · 5 g · 52 × 29 × 13 mm