Whistling is a strong sound that can give a huge boost in sports games. But also in theatre and during services. If you cannot whistle on your fingers an acorn is exactly what you’ll need. I made a modern porcelain acorn, because it works well and it sounds powerful.
I used porcelain and a leather band.
The porcelain whistle is for sale for € 20,- excl. sending costs, if you’re interested please send me an email (firstname.lastname@example.org)